Problems with sound files on 320Kbps

[FoolsTree]

Well, first of all, thanks for this awesome app.
it makes my dialy subway trip to school (15 min avg) more easier. and the battery of my psp has more time of life.
But i been having some issues playing mp3 files on 320kpbs. these files plays veeeery slowly, like a vhs tape being deteriored.
any soulution for that?

Sorry for my bad english, im behind a proxy on my school so i can't use a online english dictionary.
Greetings from Japan.