It's a FAQ: make sure, hotplug doesn't load
the OSS module by adding
usbaudio to /etc/hotplug/blacklist. Or delete the usbaudio module
file, you will neverever need it.
regardless that you're absolutely right, even if the OSS module gets
loaded the device should appear in /proc/asound/cards as soon as
snd_usb_audio gets loaded.
Best regards
ce