I'm also experiencing the same problem (I'm using Intrepid). If I set default-sample-channels = 6, the pulseaudio server crashes with a "Soft CPU time limit exhausted, terminating" message. I changed it back to 2 channels and everything is working fine now. Is there any chance a new version of pulseaudio will make it to the official Intrepid repository?
I'm also experiencing the same problem (I'm using Intrepid). If I set default- sample- channels = 6, the pulseaudio server crashes with a "Soft CPU time limit exhausted, terminating" message. I changed it back to 2 channels and everything is working fine now. Is there any chance a new version of pulseaudio will make it to the official Intrepid repository?