I tried recording something with sound with my fraps (2.3.3) and it went worked fine, it was a tiny bit off synch I think but I'm pretty sure thats just because of a bad FPS, I already sent fraps 2.3.3 to samurai for him to try out, but if anyone else has the same sort of problems I suggest trying to download fraps 2.3.3 (or hit me up on msn for it) because it works for me, it could work for you too.
(shit that last part sounds like an infomercial lol)