switched to checking buffer position to make sure its legal

desktop/src/zero1hd/rhythmbullet/desktop/graphics/ui/components/Visualizer.java

@@ -100,7 +100,7 @@ public class Visualizer extends Widget implements Disposable {
 		int pos = (int) ((alGetSourcef(sourceID, AL11.AL_SAMPLE_OFFSET))-(mm.getReadWindowSize()*mm.getChannelCount()));
 		try {
 			readWindowIndex = mm.getPlaybackIndexPosition()-1;
-			buffer.position(pos);
+			buffer.position(Math.max(pos, 0));
 		} catch (IllegalArgumentException iae) {
 			buffer.position(0);
 			Gdx.app.error("BufferPosition", iae + " position was " + pos);