diff --git a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/fragment/PlayerFragment.kt b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/fragment/PlayerFragment.kt
index 417af338..785ccd19 100644
--- a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/fragment/PlayerFragment.kt
+++ b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/fragment/PlayerFragment.kt
@@ -1079,8 +1079,7 @@ class PlayerFragment :
             Player.STATE_BUFFERING -> {
 
                 val downloadStatus = resources.getString(
-                    R.string.download_playerstate_downloading,
-                    Util.formatPercentage(progress)
+                    R.string.download_playerstate_loading
                 )
                 progressBar.secondaryProgress = progress
                 setTitle(this@PlayerFragment, downloadStatus)
diff --git a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/playback/APIDataSource.kt b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/playback/APIDataSource.kt
index f5b652ad..0a071dbe 100644
--- a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/playback/APIDataSource.kt
+++ b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/playback/APIDataSource.kt
@@ -147,7 +147,7 @@ open class APIDataSource private constructor(
         val components = dataSpec.uri.toString().split('|')
         val id = components[0]
         val bitrate = components[1].toInt()
-        val request = subsonicAPIClient.api.stream(id, bitrate, offset = 0)
+        val request = subsonicAPIClient.api.stream(id, bitrate, offset = dataSpec.position)
         val response: retrofit2.Response<ResponseBody>?
         val streamResponse: StreamResponse
 
@@ -220,7 +220,7 @@ open class APIDataSource private constructor(
 
     @Throws(HttpDataSourceException::class)
     override fun read(buffer: ByteArray, offset: Int, length: Int): Int {
-        Timber.i("APIDatasource: Read: %s %s %s", buffer, offset, length)
+        Timber.d("APIDatasource: Read: %s %s", offset, length)
         return try {
             readInternal(buffer, offset, length)
         } catch (e: IOException) {
diff --git a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/playback/CachedDataSource.kt b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/playback/CachedDataSource.kt
index e200b5f4..19789fd9 100644
--- a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/playback/CachedDataSource.kt
+++ b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/playback/CachedDataSource.kt
@@ -10,15 +10,15 @@ package org.moire.ultrasonic.playback
 import android.net.Uri
 import androidx.core.net.toUri
 import androidx.media3.common.C
+import androidx.media3.common.PlaybackException
 import androidx.media3.common.util.Util
 import androidx.media3.datasource.BaseDataSource
 import androidx.media3.datasource.DataSource
 import androidx.media3.datasource.DataSpec
-import androidx.media3.datasource.HttpDataSource
-import androidx.media3.datasource.cache.CacheDataSource
-import androidx.media3.datasource.cache.CacheDataSource.CacheIgnoredReason
+import androidx.media3.datasource.HttpDataSource.HttpDataSourceException
 import java.io.IOException
 import java.io.InputStream
+import java.io.InterruptedIOException
 import org.moire.ultrasonic.util.AbstractFile
 import org.moire.ultrasonic.util.FileUtil
 import org.moire.ultrasonic.util.Storage
@@ -26,30 +26,13 @@ import timber.log.Timber
 
 @androidx.annotation.OptIn(androidx.media3.common.util.UnstableApi::class)
 class CachedDataSource(
-    private var upstreamDataSource: DataSource,
-    private var eventListener: EventListener?
+    private var upstreamDataSource: DataSource
 ) : BaseDataSource(false) {
 
     class Factory(
         private var upstreamDataSourceFactory: DataSource.Factory
     ) : DataSource.Factory {
 
-        private var eventListener: EventListener? = null
-
-        /**
-         * Sets the {link EventListener} to which events are delivered.
-         *
-         *
-         * The default is `null`.
-         *
-         * @param eventListener The [EventListener].
-         * @return This factory.
-         */
-        fun setEventListener(eventListener: EventListener?): Factory {
-            this.eventListener = eventListener
-            return this
-        }
-
         override fun createDataSource(): CachedDataSource {
             return createDataSourceInternal(
                 upstreamDataSourceFactory.createDataSource()
@@ -60,30 +43,11 @@ class CachedDataSource(
             upstreamDataSource: DataSource
         ): CachedDataSource {
             return CachedDataSource(
-                upstreamDataSource,
-                eventListener
+                upstreamDataSource
             )
         }
     }
 
-    /** Listener of [CacheDataSource] events.  */
-    interface EventListener {
-        /**
-         * Called when bytes have been read from the cache.
-         *
-         * @param cacheSizeBytes Current cache size in bytes.
-         * @param cachedBytesRead Total bytes read from the cache since this method was last called.
-         */
-        fun onCachedBytesRead(cacheSizeBytes: Long, cachedBytesRead: Long)
-
-        /**
-         * Called when the current request ignores cache.
-         *
-         * @param reason Reason cache is bypassed.
-         */
-        fun onCacheIgnored(reason: @CacheIgnoredReason Int)
-    }
-
     private var bytesToRead: Long = 0
     private var bytesRead: Long = 0
     private var dataSpec: DataSpec? = null
@@ -94,9 +58,7 @@ class CachedDataSource(
 
     override fun open(dataSpec: DataSpec): Long {
         Timber.i(
-            "CachedDatasource: Open: %s %s %s",
-            dataSpec.uri,
-            dataSpec.position,
+            "CachedDatasource: Open: %s",
             dataSpec.toString()
         )
 
@@ -112,6 +74,8 @@ class CachedDataSource(
         if (cacheLength > 0) {
             transferInitializing(dataSpec)
             bytesToRead = cacheLength
+            transferStarted(dataSpec)
+            skipFully(dataSpec.position, dataSpec)
             return bytesToRead
         }
 
@@ -120,13 +84,14 @@ class CachedDataSource(
     }
 
     override fun read(buffer: ByteArray, offset: Int, length: Int): Int {
-        Timber.i("CachedDatasource: Read: %s %s %s", buffer, offset, length)
+        if (offset > 0 || length > 4)
+            Timber.d("CachedDatasource: Read: %s %s", offset, length)
         return if (cachePath != null) {
             try {
                 readInternal(buffer, offset, length)
             } catch (e: IOException) {
-                throw HttpDataSource.HttpDataSourceException.createForIOException(
-                    e, Util.castNonNull(dataSpec), HttpDataSource.HttpDataSourceException.TYPE_READ
+                throw HttpDataSourceException.createForIOException(
+                    e, Util.castNonNull(dataSpec), HttpDataSourceException.TYPE_READ
                 )
             }
         } else {
@@ -148,14 +113,63 @@ class CachedDataSource(
         }
         val read = Util.castNonNull(responseByteStream).read(buffer, offset, readLength)
         if (read == -1) {
+            Timber.i("CachedDatasource: EndOfInput")
             return C.RESULT_END_OF_INPUT
         }
         bytesRead += read.toLong()
-        // TODO
-        // bytesTransferred(read)
+        bytesTransferred(read)
         return read
     }
 
+    /**
+     * Attempts to skip the specified number of bytes in full.
+     *
+     * @param bytesToSkip The number of bytes to skip.
+     * @param dataSpec The [DataSpec].
+     * @throws HttpDataSourceException If the thread is interrupted during the operation, or an error
+     * occurs while reading from the source, or if the data ended before skipping the specified
+     * number of bytes.
+     */
+    @Suppress("ThrowsCount")
+    @Throws(HttpDataSourceException::class)
+    private fun skipFully(bytesToSkip: Long, dataSpec: DataSpec) {
+        var bytesToSkip = bytesToSkip
+        if (bytesToSkip == 0L) {
+            return
+        }
+        val skipBuffer = ByteArray(4096)
+        try {
+            while (bytesToSkip > 0) {
+                val readLength =
+                    bytesToSkip.coerceAtMost(skipBuffer.size.toLong()).toInt()
+                val read = Util.castNonNull(responseByteStream).read(skipBuffer, 0, readLength)
+                if (Thread.currentThread().isInterrupted) {
+                    throw InterruptedIOException()
+                }
+                if (read == -1) {
+                    throw HttpDataSourceException(
+                        dataSpec,
+                        PlaybackException.ERROR_CODE_IO_READ_POSITION_OUT_OF_RANGE,
+                        HttpDataSourceException.TYPE_OPEN
+                    )
+                }
+                bytesToSkip -= read.toLong()
+                bytesTransferred(read)
+            }
+            return
+        } catch (e: IOException) {
+            if (e is HttpDataSourceException) {
+                throw e
+            } else {
+                throw HttpDataSourceException(
+                    dataSpec,
+                    PlaybackException.ERROR_CODE_IO_UNSPECIFIED,
+                    HttpDataSourceException.TYPE_OPEN
+                )
+            }
+        }
+    }
+
     /*
      * This method is called by StatsDataSource to verify that the loading succeeded,
      * so its important that we return the correct value here..
@@ -165,9 +179,10 @@ class CachedDataSource(
     }
 
     override fun close() {
-        Timber.i("CachedDatasource: close")
+        Timber.i("CachedDatasource: close %s", openedFile)
         if (openedFile) {
             openedFile = false
+            transferEnded()
             responseByteStream?.close()
             responseByteStream = null
         }
@@ -193,6 +208,10 @@ class CachedDataSource(
         cacheFile = Storage.getFromPath(filePath)!!
         responseByteStream = cacheFile!!.getFileInputStream()
 
-        return cacheFile!!.getDocumentFileDescriptor("r")!!.length
+        val descriptor = cacheFile!!.getDocumentFileDescriptor("r")
+        val length = descriptor!!.length
+        descriptor.close()
+
+        return length
     }
 }
diff --git a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/Downloader.kt b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/Downloader.kt
index 30e75bf9..967fff92 100644
--- a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/Downloader.kt
+++ b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/Downloader.kt
@@ -68,7 +68,8 @@ class Downloader(
         override fun run() {
             try {
                 Timber.w("Checking Downloads")
-                checkDownloadsInternal()
+                // FIXME
+                // checkDownloadsInternal()
             } catch (all: Exception) {
                 Timber.e(all, "checkDownloads() failed.")
             } finally {
diff --git a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/MediaPlayerController.kt b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/MediaPlayerController.kt
index e3978c22..fa917baf 100644
--- a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/MediaPlayerController.kt
+++ b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/MediaPlayerController.kt
@@ -298,11 +298,13 @@ class MediaPlayerController(
 
     @Synchronized
     fun seekTo(position: Int) {
+        Timber.i("SeekTo: %s", position)
         controller?.seekTo(position.toLong())
     }
 
     @Synchronized
     fun seekTo(index: Int, position: Int) {
+        Timber.i("SeekTo: %s %s", index, position)
         controller?.seekTo(index, position.toLong())
     }
 
diff --git a/ultrasonic/src/main/res/values-cs/strings.xml b/ultrasonic/src/main/res/values-cs/strings.xml
index 2a8c3889..e4e015e2 100644
--- a/ultrasonic/src/main/res/values-cs/strings.xml
+++ b/ultrasonic/src/main/res/values-cs/strings.xml
@@ -62,7 +62,6 @@
     <string name="download.menu_show_album">Zobrazit album</string>
     <string name="download.menu_shuffle">Náhodně</string>
     <string name="download.menu_visualizer">Vizualizér</string>
-    <string name="download.playerstate_downloading">Stahuji - %s</string>
     <string name="download.playerstate_playing_shuffle">Přehrávám mix</string>
     <string name="download.playlist_done">Playlist úspěšně uložen.</string>
     <string name="download.playlist_error">Chyba ukládání playlistu, zkuste později.</string>
diff --git a/ultrasonic/src/main/res/values-de/strings.xml b/ultrasonic/src/main/res/values-de/strings.xml
index 03e25e43..efdf3aa2 100644
--- a/ultrasonic/src/main/res/values-de/strings.xml
+++ b/ultrasonic/src/main/res/values-de/strings.xml
@@ -76,7 +76,6 @@
     <string name="download.menu_show_album">Album anzeigen</string>
     <string name="download.menu_shuffle">Mischen</string>
     <string name="download.menu_visualizer">Grafik</string>
-    <string name="download.playerstate_downloading">Herunterladen - %s</string>
     <string name="download.playerstate_playing_shuffle">Wiedergabeliste mischen</string>
     <string name="download.playlist_done">Die Wiedergabeliste wurde gespeichert</string>
     <string name="download.playlist_error">Konnte die Wiedergabeliste nicht speichern, bitte später erneut versuchen.</string>
diff --git a/ultrasonic/src/main/res/values-es/strings.xml b/ultrasonic/src/main/res/values-es/strings.xml
index f2f44fc8..eced3d24 100644
--- a/ultrasonic/src/main/res/values-es/strings.xml
+++ b/ultrasonic/src/main/res/values-es/strings.xml
@@ -76,7 +76,6 @@
     <string name="download.menu_show_album">Mostrar Álbum</string>
     <string name="download.menu_shuffle">Aleatorio</string>
     <string name="download.menu_visualizer">Visualizador</string>
-    <string name="download.playerstate_downloading">Descargando - %s</string>
     <string name="download.playerstate_playing_shuffle">Reproduciendo en modo aleatorio</string>
     <string name="download.playlist_done">Lista de reproducción guardada con éxito.</string>
     <string name="download.playlist_error">Fallo al guardar la lista de reproducción, por favor reinténtalo mas tarde.</string>
diff --git a/ultrasonic/src/main/res/values-fr/strings.xml b/ultrasonic/src/main/res/values-fr/strings.xml
index de7d1611..111c4cd0 100644
--- a/ultrasonic/src/main/res/values-fr/strings.xml
+++ b/ultrasonic/src/main/res/values-fr/strings.xml
@@ -76,7 +76,6 @@
     <string name="download.menu_show_album">Afficher l\'album</string>
     <string name="download.menu_shuffle">Aléatoire</string>
     <string name="download.menu_visualizer">Visualiseur</string>
-    <string name="download.playerstate_downloading">Téléchargement - %s</string>
     <string name="download.playerstate_playing_shuffle">En lecture aléatoire</string>
     <string name="download.playlist_done">Playlist enregistrée avec succès !</string>
     <string name="download.playlist_error">Échec de l\'enregistrement de la playlist, veuillez réessayer plus tard.</string>
diff --git a/ultrasonic/src/main/res/values-hu/strings.xml b/ultrasonic/src/main/res/values-hu/strings.xml
index f7a43478..04e907e7 100644
--- a/ultrasonic/src/main/res/values-hu/strings.xml
+++ b/ultrasonic/src/main/res/values-hu/strings.xml
@@ -71,7 +71,6 @@
     <string name="download.menu_show_album">Ugrás az albumhoz</string>
     <string name="download.menu_shuffle">Véletlen sorrendű</string>
     <string name="download.menu_visualizer">Visualizer</string>
-    <string name="download.playerstate_downloading">Letöltés - %s</string>
     <string name="download.playerstate_playing_shuffle">Véletlen sorrendű</string>
     <string name="download.playlist_done">Lejátszási lista mentése sikeres.</string>
     <string name="download.playlist_error">Lejátszási lista mentése sikertelen, próbálja később!</string>
diff --git a/ultrasonic/src/main/res/values-it/strings.xml b/ultrasonic/src/main/res/values-it/strings.xml
index e4c1ca0c..00e94efe 100644
--- a/ultrasonic/src/main/res/values-it/strings.xml
+++ b/ultrasonic/src/main/res/values-it/strings.xml
@@ -59,7 +59,6 @@
     <string name="download.menu_show_album">Visualizza Album</string>
     <string name="download.menu_shuffle">Casuale</string>
     <string name="download.menu_visualizer">Visualizzatore</string>
-    <string name="download.playerstate_downloading">In scaricamento - %s</string>
     <string name="download.playerstate_playing_shuffle">Riproduzione casuale</string>
     <string name="download.playlist_done">Playlist salvata con successo </string>
     <string name="download.playlist_error">Impossibile salvare la playlist, riprovare più tardi.</string>
diff --git a/ultrasonic/src/main/res/values-nl/strings.xml b/ultrasonic/src/main/res/values-nl/strings.xml
index 7b7cc123..93101248 100644
--- a/ultrasonic/src/main/res/values-nl/strings.xml
+++ b/ultrasonic/src/main/res/values-nl/strings.xml
@@ -76,7 +76,6 @@
     <string name="download.menu_show_album">Album tonen</string>
     <string name="download.menu_shuffle">Willekeurig</string>
     <string name="download.menu_visualizer">Visualisatie</string>
-    <string name="download.playerstate_downloading">Bezig met downloaden - %s</string>
     <string name="download.playerstate_playing_shuffle">Bezig met willekeurig afspelen</string>
     <string name="download.playlist_done">Afspeellijst is opgeslagen.</string>
     <string name="download.playlist_error">Afspeellijst kan niet worden opgeslagen. Probeer het later opnieuw.</string>
diff --git a/ultrasonic/src/main/res/values-pl/strings.xml b/ultrasonic/src/main/res/values-pl/strings.xml
index 459080d4..745b3d31 100644
--- a/ultrasonic/src/main/res/values-pl/strings.xml
+++ b/ultrasonic/src/main/res/values-pl/strings.xml
@@ -62,7 +62,6 @@
     <string name="download.menu_show_album">Wyświetl album</string>
     <string name="download.menu_shuffle">Wymieszaj</string>
     <string name="download.menu_visualizer">Efekt wizualny</string>
-    <string name="download.playerstate_downloading">Pobieranie - %s</string>
     <string name="download.playerstate_playing_shuffle">Odtwarzanie losowe</string>
     <string name="download.playlist_done">Playlista została zapisana.</string>
     <string name="download.playlist_error">Błąd zapisu playlisty. Proszę spróbować później.</string>
diff --git a/ultrasonic/src/main/res/values-pt-rBR/strings.xml b/ultrasonic/src/main/res/values-pt-rBR/strings.xml
index 6f9098f1..7a31aba0 100644
--- a/ultrasonic/src/main/res/values-pt-rBR/strings.xml
+++ b/ultrasonic/src/main/res/values-pt-rBR/strings.xml
@@ -74,7 +74,6 @@
     <string name="download.menu_show_album">Mostrar Álbum</string>
     <string name="download.menu_shuffle">Misturar</string>
     <string name="download.menu_visualizer">Visualizador</string>
-    <string name="download.playerstate_downloading">Baixando - %s</string>
     <string name="download.playerstate_playing_shuffle">Tocando misturado</string>
     <string name="download.playlist_done">Playlist salva com sucesso.</string>
     <string name="download.playlist_error">Falha ao salvar a playlist, Tente mais tarde.</string>
diff --git a/ultrasonic/src/main/res/values-pt/strings.xml b/ultrasonic/src/main/res/values-pt/strings.xml
index 43fe5bf3..f3e6b768 100644
--- a/ultrasonic/src/main/res/values-pt/strings.xml
+++ b/ultrasonic/src/main/res/values-pt/strings.xml
@@ -62,7 +62,6 @@
     <string name="download.menu_show_album">Mostrar Álbum</string>
     <string name="download.menu_shuffle">Misturar</string>
     <string name="download.menu_visualizer">Visualizador</string>
-    <string name="download.playerstate_downloading">Descarregando - %s</string>
     <string name="download.playerstate_playing_shuffle">Tocando misturado</string>
     <string name="download.playlist_done">Playlist salva com sucesso.</string>
     <string name="download.playlist_error">Falha ao salvar a playlist, Tente mais tarde.</string>
diff --git a/ultrasonic/src/main/res/values-ru/strings.xml b/ultrasonic/src/main/res/values-ru/strings.xml
index 78490e76..fb6a8e12 100644
--- a/ultrasonic/src/main/res/values-ru/strings.xml
+++ b/ultrasonic/src/main/res/values-ru/strings.xml
@@ -76,7 +76,6 @@
     <string name="download.menu_show_album">Показать альбом</string>
     <string name="download.menu_shuffle">Случайное воспроизведение</string>
     <string name="download.menu_visualizer">Визуализатор</string>
-    <string name="download.playerstate_downloading">Загрузка - %s</string>
     <string name="download.playerstate_playing_shuffle">Игра в случайном порядке</string>
     <string name="download.playlist_done">Плейлист был успешно сохранен.</string>
     <string name="download.playlist_error">Не удалось сохранить плейлист, попробуйте позже.</string>
diff --git a/ultrasonic/src/main/res/values-zh-rCN/strings.xml b/ultrasonic/src/main/res/values-zh-rCN/strings.xml
index 3cba252c..0431a0db 100644
--- a/ultrasonic/src/main/res/values-zh-rCN/strings.xml
+++ b/ultrasonic/src/main/res/values-zh-rCN/strings.xml
@@ -76,7 +76,6 @@
     <string name="download.menu_show_album">显示专辑</string>
     <string name="download.menu_shuffle">随机</string>
     <string name="download.menu_visualizer">可视化</string>
-    <string name="download.playerstate_downloading">下载中 - %s</string>
     <string name="download.playerstate_playing_shuffle">随机播放</string>
     <string name="download.playlist_done">已成功保存播放列表。</string>
     <string name="download.playlist_error">保存播放列表失败，请重试。</string>
diff --git a/ultrasonic/src/main/res/values/strings.xml b/ultrasonic/src/main/res/values/strings.xml
index 13260419..6b60f2ba 100644
--- a/ultrasonic/src/main/res/values/strings.xml
+++ b/ultrasonic/src/main/res/values/strings.xml
@@ -78,7 +78,7 @@
     <string name="download.menu_shuffle_on">Shuffle mode enabled</string>
     <string name="download.menu_shuffle_off">Shuffle mode disabled</string>
     <string name="download.menu_visualizer">Visualizer</string>
-    <string name="download.playerstate_downloading">Downloading - %s</string>
+    <string name="download.playerstate_loading">Buffering …</string>
     <string name="download.playerstate_playing_shuffle">Playing shuffle</string>
     <string name="download.playlist_done">Playlist was successfully saved.</string>
     <string name="download.playlist_error">Failed to save playlist, please try later.</string>