make SoundMixer::playRaw only check sound IDs if you actually pass one

svn-id: r8746

1 files changed, 9 insertions, 7 deletions

diff --git a/sound/mixer.cpp b/sound/mixer.cpp
index dd7a6ede62..97f5b71ca2 100644
--- a/sound/mixer.cpp
+++ b/sound/mixer.cpp
@@ -230,13 +230,15 @@ int SoundMixer::insertChannel(PlayingSoundHandle *handle, Channel *chan) {
 
 int SoundMixer::playRaw(PlayingSoundHandle *handle, void *sound, uint32 size, uint rate, byte flags, int id) {
 	// Prevent duplicate sounds
-	_syst->lock_mutex(_mutex);	
-        for (int i = 0; i != NUM_CHANNELS; i++)
-                if (_channels[i] != NULL && _channels[i]->_id == id) {
-			_syst->unlock_mutex(_mutex);
-			return -1;
-		}
-	_syst->unlock_mutex(_mutex);
+	if (id != -1) {
+		_syst->lock_mutex(_mutex);	
+		    for (int i = 0; i != NUM_CHANNELS; i++)
+			        if (_channels[i] != NULL && _channels[i]->_id == id) {
+						_syst->unlock_mutex(_mutex);
+						return -1;
+					}
+		_syst->unlock_mutex(_mutex);
+	}
 
 	return insertChannel(handle, new ChannelRaw(this, sound, size, rate, flags, id));
 }