I know that the PS3 has problems when streaming MP4 video, but Divx usually works better. Theres also some unexplainable stuff going on when files are transcoded on the fly. Also check so your connection dont have a "bottleneck" and that it dosent run any other applications in the background.
The best way, and i hate it since im a big fan if wireless, is to connect the PS3 directly to the NAS with a cord.. if possible.








