Several people have contacted me to tell me that the latest version of OSS4 in Debian Unstable 4.2-build2007-1+nmu1 introduces several audio issues such as garbled sound or kernel panics. I can confirm I have issues as well with this version.
Downgrading to 4.2-build2007-1 fixes the problem.
I recommending putting the following in /etc/apt/preferences:
Package: oss4-base oss4-dev oss4-dkms oss4-gtkThis will prevent Debian from trying to upgrade to that version.
Pin: version 4.2-build2007-1+nmu1
If you already accidentally upgraded to it, older versions are still available.