diff --git a/src/net/java/sip/communicator/impl/neomedia/MediaStreamImpl.java b/src/net/java/sip/communicator/impl/neomedia/MediaStreamImpl.java
index 2d02d5bed..0388febba 100644
--- a/src/net/java/sip/communicator/impl/neomedia/MediaStreamImpl.java
+++ b/src/net/java/sip/communicator/impl/neomedia/MediaStreamImpl.java
@@ -1360,30 +1360,29 @@ private void setRemoteSourceID(long ssrc)
      * return an empty <tt>List</tt> in case this stream is not part of a mixed
      * conference call.
      *
-     * @return a <tt>List</tt> of CSRC IDs for parties that are currently known
-     * to contribute to the media that this stream is currently streaming or
-     * an empty <tt>List</tt> in case this <tt>MediaStream</tt> is not part of
-     * a conference call.
+     * @return a <tt>List</tt> array of CSRC IDs stored as <tt>Long</tt>
+     * instances and representing parties that are currently known to contribute
+     * to the media that this stream or an empty <tt>List</tt> in case this
+     * <tt>MediaStream</tt> is not part of a conference call.
      */
-    public List<String> getLocalContributingSourceIDs()
+    public List<Long> getLocalContributingSourceIDs()
     {
-        List<String> csrcList = new ArrayList<String>();
+        if( this.deviceSession == null)
+            return null;
 
         MediaDeviceSession deviceSession = getDeviceSession();
-        if( this.deviceSession != null)
-            csrcList.addAll( deviceSession.getRemoteSSRCList() );
 
-        Iterator<String> csrcIter = csrcList.iterator();
+        long[] ssrcArray = deviceSession.getRemoteSSRCList();
+
+        List<Long> csrcList = new ArrayList<Long>(ssrcArray.length);
 
         //in case of a conf call the mixer would return all SSRC IDs that are
         //currently contributing including this stream's counterpart. This
         //method is about
-        while(csrcIter.hasNext())
+        for(long csrc : ssrcArray)
         {
-            String csrc = csrcIter.next();
-
-            if (csrc.equals(getRemoteSourceID()))
-                csrcIter.remove();
+            if (csrc != this.getRemoteSourceID())
+                csrcList.add(csrc);
         }
 
         return csrcList;
@@ -1398,10 +1397,12 @@ public List<String> getLocalContributingSourceIDs()
      * contributing to the stream that we are receiving from this
      * <tt>MediaStream</tt>'s remote party.
      */
-    public List<String> getRemoteContributingSourceIDs()
+    public long[] getRemoteContributingSourceIDs()
     {
-        List<String> csrcList = new ArrayList<String>();
+        long[] remoteSsrcList = getDeviceSession().getRemoteSSRCList();
 
-        return csrcList;
+        //todo -implement
+
+        return remoteSsrcList;
     }
 }
diff --git a/src/net/java/sip/communicator/impl/neomedia/device/AudioMixerMediaDevice.java b/src/net/java/sip/communicator/impl/neomedia/device/AudioMixerMediaDevice.java
index e69787a30..041075987 100644
--- a/src/net/java/sip/communicator/impl/neomedia/device/AudioMixerMediaDevice.java
+++ b/src/net/java/sip/communicator/impl/neomedia/device/AudioMixerMediaDevice.java
@@ -449,12 +449,12 @@ public void removeReceiveStream(ReceiveStream receiveStream)
          * a pseudo device we would simply be delegating the call to the
          * corresponding method of the master mixer device session.
          *
-         * @return a <tt>List</tt> of SSRC identifiers (in a hexadecimal
-         * <tt>String</tt> form) that are currently contributing to the mixer
-         * encapsulated by this device session.
+         * @return a <tt>long[]</tt> array of SSRC identifiers that are
+         * currently contributing to the mixer encapsulated by this device
+         * session.
          */
         @Override
-        public List<String> getRemoteSSRCList()
+        public long[] getRemoteSSRCList()
         {
             return audioMixerMediaDeviceSession.getRemoteSSRCList();
         }
diff --git a/src/net/java/sip/communicator/impl/neomedia/device/MediaDeviceSession.java b/src/net/java/sip/communicator/impl/neomedia/device/MediaDeviceSession.java
index 53412dfb4..9d967cbef 100644
--- a/src/net/java/sip/communicator/impl/neomedia/device/MediaDeviceSession.java
+++ b/src/net/java/sip/communicator/impl/neomedia/device/MediaDeviceSession.java
@@ -224,8 +224,7 @@ protected void addReceiveStream(
 
         receiveStreams.put(receiveStream, receiveStreamDataSource);
         if (logger.isTraceEnabled())
-            logger
-                .trace(
+            logger.trace(
                     "Added ReceiveStream with ssrc " + receiveStream.getSSRC());
 
         synchronized (players)
@@ -250,15 +249,13 @@ protected void addReceiveStream(
                 }
 
                 if (exception != null)
-                    logger
-                        .error(
+                    logger.error(
                             "Failed to create player"
                                 + " for ReceiveStream with ssrc "
                                 + receiveStream.getSSRC(),
                             exception);
                 else if (!waitForState(player, Processor.Configured))
-                    logger
-                        .error(
+                    logger.error(
                             "Failed to configure player"
                                 + " for ReceiveStream with ssrc "
                                 + receiveStream.getSSRC());
@@ -1373,18 +1370,19 @@ private static boolean waitForState(Processor processor, int state)
      * to query a device session operating over a mixer in which case we would
      * have the SSRC IDs of all parties currently contributing to the mixing.
      *
-     * @return a <tt>List</tt> of SSRC identifiers (in a hexadecimal
-     * <tt>String</tt> form) that this device session is.
-     * handling streams from.
+     * @return a <tt>long[]</tt> array of SSRC identifiers that this device
+     * session is handling streams from.
      */
-    public List<String> getRemoteSSRCList()
+    public long[] getRemoteSSRCList()
     {
-        Set<ReceiveStream> streams = this.receiveStreams.keySet();
-        List<String> ssrcIDList = new ArrayList<String>();
+        List<ReceiveStream> streams
+            = new LinkedList<ReceiveStream>(this.receiveStreams.keySet());
+        long[] ssrcIDList = new long[streams.size()];
 
-        for ( ReceiveStream stream : streams)
+        for ( int i = 0; i < ssrcIDList.length; i++)
         {
-            ssrcIDList.add(Long.toHexString(stream.getSSRC()));
+            ReceiveStream stream = streams.get(i);
+            ssrcIDList[i] = stream.getSSRC();
         }
 
         return ssrcIDList;
diff --git a/src/net/java/sip/communicator/impl/neomedia/transform/csrc/CsrcTransformEngine.java b/src/net/java/sip/communicator/impl/neomedia/transform/csrc/CsrcTransformEngine.java
index d478c78b1..518de2b63 100644
--- a/src/net/java/sip/communicator/impl/neomedia/transform/csrc/CsrcTransformEngine.java
+++ b/src/net/java/sip/communicator/impl/neomedia/transform/csrc/CsrcTransformEngine.java
@@ -10,24 +10,35 @@
 import net.java.sip.communicator.impl.neomedia.transform.*;
 
 /**
+ * We use this engine to add the list of CSRC identifiers in RTP packets that
+ * we send to conference participants during calls where we are the mixer.
+ *
  * @author Emil Ivov
  */
 public class CsrcTransformEngine
     implements TransformEngine,
                PacketTransformer
 {
+    /**
+     * The <tt>MediaStreamImpl</tt> that this transform engine was created to
+     * transform packets fro.
+     */
+    private final MediaStreamImpl mediaStream;
 
-    /* (non-Javadoc)
-     * @see net.java.sip.communicator.impl.neomedia.transform.TransformEngine#getRTCPTransformer()
+    /**
+     * Creates
+     * @param stream
      */
+    public CsrcTransformEngine(MediaStreamImpl stream)
+    {
+        this.mediaStream = stream;
+    }
+
     public PacketTransformer getRTCPTransformer()
     {
         return null;
     }
 
-    /* (non-Javadoc)
-     * @see net.java.sip.communicator.impl.neomedia.transform.TransformEngine#getRTPTransformer()
-     */
     public PacketTransformer getRTPTransformer()
     {
         return this;