media_bug: Fix for rare race condition. More work required to make media bug safe.

src/switch_core_io.c

@@ -346,13 +346,16 @@ SWITCH_DECLARE(switch_status_t) switch_core_session_read_frame(switch_core_sessi
 					memset(session->raw_read_frame.data, 255, session->raw_read_frame.datalen);
 					status = SWITCH_STATUS_SUCCESS;
 				} else {
-					status = switch_core_codec_decode(use_codec,
+					switch_thread_rwlock_rdlock(session->bug_rwlock);
+					status = switch_core_codec_decode(use_codec->implementation?use_codec:read_frame->codec,
 													  session->read_codec,
 													  read_frame->data,
 													  read_frame->datalen,
 													  session->read_impl.actual_samples_per_second,
 													  session->raw_read_frame.data, &session->raw_read_frame.datalen, &session->raw_read_frame.rate, 
 													  &read_frame->flags);
+					switch_thread_rwlock_unlock(session->bug_rwlock);
+
 				}
 				
 				if (status == SWITCH_STATUS_SUCCESS) {