private void freeChannel(int index) {
        if (index == nextChannelIndex - 1) {
            nextChannelIndex--;
        } else {
            freeChannels.add(index);
        }
    }
Applies all parameters from the listener object to OpenAL.
@param listener The listener object.
jme3-core/src/main/java/com/jme3/audio/openal/ALAudioRenderer.java