Well I didn't have any really great ideas to start with. The next thing I think I'd do in your situation is look at the contents of other related files. For me, ls /etc/mod* shows that I have 4 files that start with mod and all appear to be related. I've got modules, modprobe.conf, modprobe.devfs, and modprobe.preload. If I were you I might look at those files and see if they have anything that might give you a clue. In particular, pay attention to anything having to do with sound.
If I were desperate I might do something like,
grep blacklist /etc/rc.d/*
grep blacklist /etc/init.d/*
grep blacklist /var/log/*
but this is that desperation maneuver when you have no idea what the heck to do, and you're just trying to get some clues.
If you're unfamiliar with grep, it searches the text of the files listed for any occurance of the "pattern". The pattern is blacklist. So those commands will check your initialization scripts and the majority of your log files for the occurance of the word. The next step would be to check out any files that it finds... I'd suggest something like kate with an easy to use "find" function so that you can track down the proper part of the file quickly (some of these text files might be hundreds or thousands of pages long). Also, grep will take a LONG time when used on this many files. That's a lot of text to search through. This may not really help you at all, but like I said, I don't really have any "good" ideas.