diff --git a/src/ripper/ripper.cpp b/src/ripper/ripper.cpp
index cca18c380..d07408efd 100644
--- a/src/ripper/ripper.cpp
+++ b/src/ripper/ripper.cpp
@@ -60,6 +60,10 @@ Ripper::~Ripper() { cdio_destroy(cdio_); }
 void Ripper::AddTrack(int track_number, const QString& title,
                       const QString& transcoded_filename,
                       const TranscoderPreset& preset) {
+  if (track_number < 1 || track_number > TracksOnDisc()) {
+    qLog(Warning) << "Invalid track number:" << track_number << "Ignoring";
+    return;
+  }
   TrackInformation track(track_number, title, transcoded_filename, preset);
   tracks_.append(track);
 }
@@ -67,7 +71,12 @@ void Ripper::AddTrack(int track_number, const QString& title,
 void Ripper::SetAlbumInformation(const QString& album, const QString& artist,
                                  const QString& genre, int year, int disc,
                                  Song::FileType type) {
-  album_ = AlbumInformation(album, artist, genre, year, disc, type);
+  album_.album = album;
+  album_.artist = artist;
+  album_.genre = genre;
+  album_.year = year;
+  album_.disc = disc;
+  album_.type = type;
 }
 
 int Ripper::TracksOnDisc() const {
@@ -88,7 +97,9 @@ bool Ripper::CheckCDIOIsValid() {
   cdio_ = cdio_open(NULL, DRIVER_UNKNOWN);
   // Refresh the status of the cd media. This will prevent unnecessary
   // rebuilds of the track list table.
-  cdio_get_media_changed(cdio_);
+  if (cdio_) {
+    cdio_get_media_changed(cdio_);
+  }
   return cdio_;
 }
 
diff --git a/src/ripper/ripper.h b/src/ripper/ripper.h
index 1f0eeec18..02b37d115 100644
--- a/src/ripper/ripper.h
+++ b/src/ripper/ripper.h
@@ -28,22 +28,40 @@
 
 class QFile;
 
+// Rips selected tracks from an audio CD, transcodes them to a chosen
+// format, and finally tags the files with the supplied metadata.
+//
+// Usage: Add tracks with AddTrack() and album metadata with
+// SetAlbumInformation(). Then start the ripper with Start(). The ripper
+// emits the Finished() signal when it's done or the Cancelled()
+// signal if the ripping has been cancelled.
 class Ripper : public QObject {
   Q_OBJECT
 
  public:
   explicit Ripper(QObject* parent = nullptr);
   ~Ripper();
+
+  // Adds a track to the rip list if the track number corresponds to a
+  // track on the audio cd. The track will transcoded according to the
+  // chosen TranscoderPreset.
   void AddTrack(int track_number, const QString& title,
                 const QString& transcoded_filename,
                 const TranscoderPreset& preset);
+  // Sets album metadata. This information is used when tagging the
+  // final files.
   void SetAlbumInformation(const QString& album, const QString& artist,
                            const QString& genre, int year, int disc,
                            Song::FileType type);
+  // Returns the number of audio tracks on the disc.
   int TracksOnDisc() const;
+  // Returns the number of tracks added to the rip list.
   int AddedTracks() const;
+  // Clears the rip list.
   void ClearTracks();
+  // Returns true if a cd device was successfully opened.
   bool CheckCDIOIsValid();
+  // Returns true if the cd media has changed.
   bool MediaChanged() const;
 
 signals:
@@ -81,16 +99,7 @@ signals:
   };
 
   struct AlbumInformation {
-    AlbumInformation(const QString& album = QString(),
-                     const QString& artist = QString(),
-                     const QString& genre = QString(), int year = 0,
-                     int disc = 0, Song::FileType type = Song::Type_Unknown)
-        : album(album),
-          artist(artist),
-          genre(genre),
-          year(year),
-          disc(disc),
-          type(type) {}
+    AlbumInformation() : year(0), disc(0), type(Song::Type_Unknown) {}
 
     QString album;
     QString artist;