How to probe what application does in kernel (with sound device)?

[Yuri]

I have linux skype that complains that it can't use sound device without 
giving any details.
'truss -f' flag doesn't show any system calls related to sound device 
(/dev/dsp*). Maybe it's because of child processes aren't really 
monitored by truss for linux processes.
But sound from another sound application gets some strange interruption 
and buzz every time I try to activate sound from skype. That's how I 
know that skype really does something with sound device.

Is there a way to probe program's activity with devices in-kernel?

Yuri