Get a second sound card! USB headsets usually got one integrated.
This might seem a little over the top but in my experience it’s really the only way that really works most of the time without using non or bad working wrappers.
TeamSpeak2 uses the Open Sound System “OSS” which got, let’s just say some issues with mixing, and people have to use workarounds to get it working together with games, audio players, wine. Most of them using ALSA or even OSS themselves. Those workarounds are using so called wrappers like alsa-oss “aoss”, or padsp and tweaking configuration files.
In the end, you get it working only to get to listen to the stuttering voices of your fellow TeamSpeak users or greeting them with crackling noises or echo sounds in the background of your own audio input. If, big if, you get it to work at all.
Do yourself a favour, don’t spend hours looking for solutions that won’t work, and don’t cause yourself or others headaches:
- Spend 15€ on a second sound card or 40€ on a decent USB headset
- Run TeamSpeak without a wrapper and do without any other sounds
- TeamSpeak is proprietary, get your buddies to use Mumble/Murmur (it’s better anyway)
Or wait for the overdue release of TeamSpeak3, which will use ALSA. It will still be proprietary, so you should really try getting your buddies to use Mumble.