Running Alsa 1.0.5-R3 / 1.0.5a and libmpeg3 1.5.2

Started getting scratchy audio whenever alsa is used for playing any type of mpeg audio, for example avi files. I haven't seen this happen with any other type of audio. This problem originally occured after running an emerge update, and I've checked all the mixer levels and everything else. Running the DMIX plugin on an A7N8X-E Deluxe, and nothing I do seems to have any effect on it. The fact that ARTS will play the same files with no problem makes me think that the issue is not with libmpeg3, so I'm a bit confused as to what's going on with alsa.

Edit - Just tried an MP3 with alsa, and there's no problem, so now I'm thinking it has to do with ac3. The problem still persists however with an SVCD mpeg file.

Edit: Fixed -- Apparently ALSA had some sort of problem downsampling to 44khz, changed to 48 in asoundrc