Strange, are you sure at it was the OSS driver, not the OSS emulation mode of the alsa driver. You can look at the output from "lsmod".
If the sound drivers begin with snd-..., you are using alsa, even with oss programs.
I have an Audigy 2 and I use only the alsa driver and jack for serious audio work.
If you want to do serious audio work, I can only recommand you to try Agnula/DeMuDi, a linux distro focused on professionnal audio work.
http://demudi.agnula.org/