I am having a problem with the audio after exporting videos to psp format. I've tried converting the files to other formats before exporting but the sound is the same. The sound is fine prior to exporting.

Please describe what problem you have with the audio, as it is not clear from your description. Too soft, too laud, absent, deformed, out of sync, partial, etc? Do you experience this on the PSP or in a software player on your Mac?