I have faced problems getting ALSA to do everything I want. So I switched to OSS instead. I must say, OSS has been way better that ALSA. But little did I know about the potential problems when I recently upgraded from Hardy to Intrepid. It seems that Ubuntu (to be more specific Kubuntu) has undergone some changes in the way packaged are organized (Just my guess....) . Even adept-manager has changed its name to just "adept" with "manager" as a command line argument. So basically (k)ubuntu won't upgrade/remove my existing OSS. Fine. But It couldn't even detect it. Worst, It assumed that there is no sound system so installed alsa. WTF ?
So I had this OSS installation which ubuntu was agnostic about. I had another alsa installed which for some reason never worked. Ubuntu won't let me remove existing OSS. It won't let me install the fresh one. I got following looking errors :

/var/lib/dpkg/info/oss-linux.prerm: 3: source: not found
... and several others

So basically I was stuck in a deadlock. From the error I kinda assumed that it has got to do something with the installer/uninstaller scripts (or related files) being misplaced. So I manually removed (after taking a backup ofc) all the oss related files (/var/lib/dpkg/info/oss-linux*) from package database. Just tried to install the oss again

sudo dpkg -i oss-linux-4.1-1051_amd64.deb

Voila... dpkg assumed that my previous package files were corrupted but did a fresh reinstall. Ofc I did get this ominous looking (serious) warning:

dpkg: serious warning: files list file for package `oss-linux' missing, assuming package has no files currently installed.

But in end of the it did what I wanted to.

I still do not know if there is a correct way of doing this. Please note that we are actually fiddling with package manager's files which may cause very serious problems. If anyone knows a better/correct way, please let me know.

The main point of this post is to document my experience. Because I didn't find anyone else who had faced a similar problem. So this may be of some help to someone who is facing similar problems.