diff --git a/core/src/main/java/de/danoeh/antennapod/core/syndication/handler/HandlerState.java b/core/src/main/java/de/danoeh/antennapod/core/syndication/handler/HandlerState.java
index 530cbd0e9..1cd05aa26 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/syndication/handler/HandlerState.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/syndication/handler/HandlerState.java
@@ -37,7 +37,7 @@ public class HandlerState {
     /**
      * Buffer for saving characters.
      */
-    StringBuffer contentBuf;
+    protected StringBuilder contentBuf;
 
     /**
      * Temporarily saved objects.
@@ -97,7 +97,7 @@ public class HandlerState {
         return third;
     }
 
-    public StringBuffer getContentBuf() {
+    public StringBuilder getContentBuf() {
         return contentBuf;
     }
 
diff --git a/core/src/main/java/de/danoeh/antennapod/core/syndication/handler/SyndHandler.java b/core/src/main/java/de/danoeh/antennapod/core/syndication/handler/SyndHandler.java
index 17b2708aa..ab66b912b 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/syndication/handler/SyndHandler.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/syndication/handler/SyndHandler.java
@@ -33,7 +33,7 @@ class SyndHandler extends DefaultHandler {
 	@Override
 	public void startElement(String uri, String localName, String qName,
 			Attributes attributes) throws SAXException {
-		state.contentBuf = new StringBuffer();
+		state.contentBuf = new StringBuilder();
 		Namespace handler = getHandlingNamespace(uri, qName);
 		if (handler != null) {
 			SyndElement element = handler.handleElementStart(localName, state,
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/id3reader/ChapterReader.java b/core/src/main/java/de/danoeh/antennapod/core/util/id3reader/ChapterReader.java
index 36588102c..f681b8062 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/id3reader/ChapterReader.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/id3reader/ChapterReader.java
@@ -43,7 +43,7 @@ public class ChapterReader extends ID3Reader {
 						currentChapter = null;
 					}
 				}
-				StringBuffer elementId = new StringBuffer();
+				StringBuilder elementId = new StringBuilder();
 				readISOString(elementId, input, Integer.MAX_VALUE);
 				char[] startTimeSource = readBytes(input, 4);
 				long startTime = ((int) startTimeSource[0] << 24)
@@ -54,7 +54,7 @@ public class ChapterReader extends ID3Reader {
 				return ID3Reader.ACTION_DONT_SKIP;
 			case FRAME_ID_TITLE:
 				if (currentChapter != null && currentChapter.getTitle() == null) {
-					StringBuffer title = new StringBuffer();
+					StringBuilder title = new StringBuilder();
 					readString(title, input, header.getSize());
 					currentChapter
 							.setTitle(title.toString());
@@ -67,7 +67,7 @@ public class ChapterReader extends ID3Reader {
 				if (currentChapter != null) {
 					// skip description
 					int descriptionLength = readString(null, input, header.getSize());
-					StringBuffer link = new StringBuffer();
+					StringBuilder link = new StringBuilder();
 					readISOString(link, input, header.getSize() - descriptionLength);
 					String decodedLink = URLDecoder.decode(link.toString(), "UTF-8");
 
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/id3reader/ID3Reader.java b/core/src/main/java/de/danoeh/antennapod/core/util/id3reader/ID3Reader.java
index 077d8724d..7290b9d98 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/id3reader/ID3Reader.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/id3reader/ID3Reader.java
@@ -170,7 +170,7 @@ public class ID3Reader {
         return out;
     }
 
-	int readString(StringBuffer buffer, InputStream input, int max) throws IOException,
+	protected int readString(StringBuilder buffer, InputStream input, int max) throws IOException,
 			ID3ReaderException {
 		if (max > 0) {
 			char[] encoding = readBytes(input, 1);
@@ -191,9 +191,8 @@ public class ID3Reader {
 		}
 	}
 
-	int readISOString(StringBuffer buffer, InputStream input, int max)
-			throws IOException {
-
+	protected int readISOString(StringBuilder buffer, InputStream input, int max)
+			throws IOException, ID3ReaderException {
 		int bytesRead = 0;
 		char c;
 		while (++bytesRead <= max && (c = (char) input.read()) > 0) {
@@ -204,8 +203,8 @@ public class ID3Reader {
 		return bytesRead;
 	}
 
-	private int readUnicodeString(StringBuffer strBuffer, InputStream input, int max, Charset charset)
-			throws IOException {
+	private int readUnicodeString(StringBuilder strBuffer, InputStream input, int max, Charset charset)
+			throws IOException, ID3ReaderException {
 		byte[] buffer = new byte[max];
         int c, cZero = -1;
         int i = 0;