[Alug] Can someone help with an audio problem

I have just installed KMidi. I can play midi files as Root but if I try as a user I get "Can't open output device". All audio devices in /dev are set rw for owner and rw for group 'audio'. My user is in the 'audio' group. What seems strange to me is that apparently KMidi is a front end to Timidity and I can play midi files using Timidity as a user. I've run out of ideas. Anyone? Barry Samuels