[LAU] HDSP 9632 issues

Hi. I've read a lot of archived posts about issues with this card, but none of them have solved what seems to be a fairly basic problem. I'm using Ubuntu Feisty 7.04, ALSA 1.0.14 and HDSPMixer 1.6. The HDSP 9632 has firmware 1.53. Everything seems fine -- the card is recognised, and it even makes sound using aplay. This leads me to think that there's no problem with the driver or firmware. I cannot, however, get the card to make sound using alsaplayer (there are no errors, just no sound) or SuperCollider (the jack connections are reported as fine, but again no sound). I've been beating my head against this for days, but have not had any luck. Any help/suggestions would be most welcome.