I own a Terratec DMX 6fire (ICE1712 chipset), which has for 12 analog channels (6 input / 6 output), but requires a quite complicated ALSA setup - read: manual fiddling with configuration files - for access to all channels and a usable dmix setup. Same for Pulseaudio, although I thought this was developed with the promise of doing away with such messy fiddling. In both cases I was disappointed either by low mixing quality, latencies, clicking / popping. Additionally, Pulse is only really intended for the per-user per-session use case, which was quite a problem for me as I use a system-wide MPD (Music Player Daemon) running independently of my current X / console logins.

Fortunately, Debian Squeeze has included a port of OSS4, which not only detected my card, but also provided exactly the controls — mixers, i/o routing, rate settings — that I needed and nothing superfluous (see screenshot), plus a virtual mixer running in kernel space with no need for manual multi-user setup. The ugly clicks and pops I experienced with ALSA / Pulse under high system load are gone — at least I didn't experience them in the last 3-4 days since switching, despite playing Football Manager 2011 via Wine…

Drawbacks?

1. Some applications, e.g. Chromium, only provide a ALSA sound backend. Thus, I had to (re)install libasound2-plugins and a rudimentary /etc/asound.conf:

     pcm.!default
     {
       type oss
       device /dev/dsp
     }
     mixer.!default
     {
       type oss
       device /dev/dsp
     }
   

2. Driver modules reside outside the kernel and have to be compiled. With the Debian packages, this is done automatically using DKMS.

3. Recording with Audacity doesn't really work. But the included CLI tool ossrecord works just as well. In fact, I recorded some vinyl with 32bit/96kHz sampling, something I never achieved with ALSA without major configuration fiddling. And vinyl recording was one of the main reason why I bought such a "high-end" card.