I have a flashtrax XT and I have successfully re-encoded DVD films, AVIs, mpegs and DIVX that play on it with no problems at all. However...

I decided to recode videos (AVIs) from a magazine CD to watch on it. I have tried this several ways, to AVI, DIVX, XVID, and MP4 (ipod format) and although they play fine on a PC (and on an iPod) the audio is far too slow on the flashtrax (I think the video might be the right speed but I am not positive). Interestingly, the original avi has a frame rate of 4fps which I think might be part of the issue. Although I have played around with the encoding process and have read about the encoding, I am still at a loss. Perhaps I just need to play around with the encoding process a bit more, but any suggestions as to what part is a fault or a potential way forward would be appreciated.