Volume control problem with 5.1 firewire sound interfaces

[rphogue]

When I play a DVD through a 5.1 audio interface - both Apogee Ensemble and Motu, I do not have any control over the volume through the volume control knob - it is full blast. I did not get that with earlier versions of VLC media player, and the problem is specific to VLC media player, other apps do not cause this problem.