diff --git a/trunk/src/app/srs_app_recv_thread.hpp b/trunk/src/app/srs_app_recv_thread.hpp
index 9a4dcb5e80..b986b8bd63 100644
--- a/trunk/src/app/srs_app_recv_thread.hpp
+++ b/trunk/src/app/srs_app_recv_thread.hpp
@@ -61,8 +61,9 @@ class ISrsMessageHandler
     */
     virtual bool can_handle() = 0;
     /**
-    * process the received message.
-    */
+     * process the received message.
+     * @remark user must free this message.
+     */
     virtual int handle(SrsCommonMessage* msg) = 0;
     /**
     * when recv message error.
diff --git a/trunk/src/app/srs_app_rtmp_conn.cpp b/trunk/src/app/srs_app_rtmp_conn.cpp
index e2613343a4..b08f01d813 100644
--- a/trunk/src/app/srs_app_rtmp_conn.cpp
+++ b/trunk/src/app/srs_app_rtmp_conn.cpp
@@ -916,7 +916,6 @@ int SrsRtmpConn::handle_publish_message(SrsSource* source, SrsCommonMessage* msg
             srs_error("fmle decode unpublish message failed. ret=%d", ret);
             return ret;
         }
-
         SrsAutoFree(SrsPacket, pkt);
 
         // for flash, any packet is republish.
diff --git a/trunk/src/app/srs_app_source.cpp b/trunk/src/app/srs_app_source.cpp
index 2aa5e157ec..6c853533ed 100755
--- a/trunk/src/app/srs_app_source.cpp
+++ b/trunk/src/app/srs_app_source.cpp
@@ -604,15 +604,15 @@ int SrsGopCache::cache(SrsSharedPtrMessage* shared_msg)
 
     // the gop cache know when to gop it.
     SrsSharedPtrMessage* msg = shared_msg;
-
-    // disable gop cache when not h.264
-    if (!SrsFlvCodec::video_is_h264(msg->payload, msg->size)) {
-        srs_info("gop donot cache video for none h.264");
-        return ret;
-    }
     
     // got video, update the video count if acceptable
     if (msg->is_video()) {
+        // drop video when not h.264
+        if (!SrsFlvCodec::video_is_h264(msg->payload, msg->size)) {
+            srs_info("gop cache drop video for none h.264");
+            return ret;
+        }
+        
         cached_video_count++;
         audio_after_last_video_count = 0;
     }
@@ -1464,11 +1464,25 @@ int SrsSource::on_audio(SrsCommonMessage* shared_audio)
     }
     srs_info("Audio dts=%"PRId64", size=%d", msg.timestamp, msg.size);
     
+    // directly process the audio message.
     if (!mix_correct) {
         return on_audio_imp(&msg);
     }
     
-    return do_mix_correct(&msg);
+    // insert msg to the queue.
+    mix_queue->push(msg.copy());
+    
+    // fetch someone from mix queue.
+    SrsSharedPtrMessage* m = mix_queue->pop();
+    if (!m) {
+        return ret;
+    }
+    
+    // consume the monotonically increase message.
+    ret = on_audio_imp(m);
+    srs_freep(m);
+    
+    return ret;
 }
 
 int SrsSource::on_audio_imp(SrsSharedPtrMessage* msg)
@@ -1628,11 +1642,26 @@ int SrsSource::on_video(SrsCommonMessage* shared_video)
     }
     srs_info("Video dts=%"PRId64", size=%d", msg.timestamp, msg.size);
     
+    // directly process the audio message.
     if (!mix_correct) {
         return on_video_imp(&msg);
     }
     
-    return do_mix_correct(&msg);
+    // insert msg to the queue.
+    mix_queue->push(msg.copy());
+    
+    // fetch someone from mix queue.
+    SrsSharedPtrMessage* m = mix_queue->pop();
+    if (!m) {
+        return ret;
+    }
+    SrsAutoFree(SrsSharedPtrMessage, m);
+    
+    // consume the monotonically increase message.
+    ret = on_video_imp(m);
+    srs_freep(m);
+    
+    return ret;
 }
 
 int SrsSource::on_video_imp(SrsSharedPtrMessage* msg)
@@ -1766,29 +1795,6 @@ int SrsSource::on_video_imp(SrsSharedPtrMessage* msg)
     return ret;
 }
 
-int SrsSource::do_mix_correct(SrsSharedPtrMessage* msg)
-{
-    int ret = ERROR_SUCCESS;
-    
-    // insert msg to the queue.
-    mix_queue->push(msg->copy());
-    
-    // fetch someone from mix queue.
-    SrsSharedPtrMessage* m = mix_queue->pop();
-    if (!m) {
-        return ret;
-    }
-    SrsAutoFree(SrsSharedPtrMessage, m);
-    
-    // consume the monotonically increase message.
-    if (m->is_audio()) {
-        return on_audio_imp(m);
-    }
-    
-    srs_assert(m->is_video());
-    return on_video_imp(m);
-}
-
 int SrsSource::on_aggregate(SrsCommonMessage* msg)
 {
     int ret = ERROR_SUCCESS;
diff --git a/trunk/src/app/srs_app_source.hpp b/trunk/src/app/srs_app_source.hpp
index f7a75d4ac9..1f6d1c0fc8 100644
--- a/trunk/src/app/srs_app_source.hpp
+++ b/trunk/src/app/srs_app_source.hpp
@@ -536,8 +536,6 @@ class SrsSource : public ISrsReloadHandler
     virtual int on_video(SrsCommonMessage* video);
 private:
     virtual int on_video_imp(SrsSharedPtrMessage* video);
-private:
-    virtual int do_mix_correct(SrsSharedPtrMessage* msg);
 public:
     virtual int on_aggregate(SrsCommonMessage* msg);
     /**
diff --git a/trunk/src/protocol/srs_protocol_buffer.cpp b/trunk/src/protocol/srs_protocol_buffer.cpp
index 24e64a48fb..1761312822 100644
--- a/trunk/src/protocol/srs_protocol_buffer.cpp
+++ b/trunk/src/protocol/srs_protocol_buffer.cpp
@@ -97,8 +97,8 @@ void SrsFastBuffer::set_buffer(int buffer_size)
     }
     
     // realloc for buffer change bigger.
-    int start = p - buffer;
-    int nb_bytes = end - p;
+    int start = (int)(p - buffer);
+    int nb_bytes = (int)(end - p);
     
     buffer = (char*)realloc(buffer, nb_resize_buf);
     nb_buffer = nb_resize_buf;