Some of us playing Unreal Tournament 2004 may be familiar with the error open /dev/[sound/]dsp: Resource temporarily unavailable. This is usually caused because the sound system is busy (for example, you have an audio player opened, or a paused movie).
The simplest way to get over this problem is to install the alsa-oss package, which contains the aoss wrapper to allow the use of ALSA OSS library. In Debian, type as root:
apt-get install alsa-oss
Then run UT2004 like this:
Depending on where your game is installed. The good thing about this is that you can now listen to music in a player separate from the one included in the game and also hear the UT2004 sounds.