diff --git a/src/org/czentral/incubator/streamm/PublisherAppInstance.java b/src/org/czentral/incubator/streamm/PublisherAppInstance.java
index db196f8..e43a727 100644
--- a/src/org/czentral/incubator/streamm/PublisherAppInstance.java
+++ b/src/org/czentral/incubator/streamm/PublisherAppInstance.java
@@ -335,8 +335,9 @@ public void mediaChunk(MessageInfo mi, byte[] readBuffer, int payloadOffset, int
                         + "." + audioObjectType;
 
                 int timescale = ((Double)metaData.get("audiosamplerate")).intValue();
+                int audioSampleSize = metaData.containsKey("audiosamplesize") ? ((Double)metaData.get("audiosamplesize")).intValue() : 16;
                 int newTrackID = header.addAudioTrack(((Double)metaData.get("audiosamplerate")).intValue()
-                        , ((Double)metaData.get("audiosamplesize")).intValue()
+                        , audioSampleSize
                         , ((Double)metaData.get("audiodatarate")).intValue()
                         , decoderSpecificBytes);