Media Player Problem

[Guest andyhunt]

Hi

I have an O2 XDA SP.

I have a 1gb mini SD card to store music and the like.

I have uploaded lots of music to my mobile (on the mini SD card).

When playing music, some of the music files will not play.

The Alert says "Cannot play the file becasue the licence is not valid or is corrupted"

All the music is fully licenced (was downloaded and paid for on MSN music) and it plays perfect on my computer.

Is this a bug or a known issue and more importantly, is there a solution?

Cheers

Andy