when closing audio source, don't flush audio data if audio buffer is empty

sesman/chansrv/sound.c

@@ -493,11 +493,14 @@ sound_send_close(void)
     LOG(10, ("sound_send_close:"));
 
     /* send any left over data */
+    if (g_buf_index)
+    {
         if (sound_send_wave_data_chunk(g_buffer, g_buf_index) != 0) 
         {
             LOG(10, ("sound_send_close: sound_send_wave_data_chunk failed"));
             return 1;
         }
+    }
     g_buf_index = 0;
     g_memset(g_sent_flag, 0, sizeof(g_sent_flag));