Doppelgangers and stuff

[Tony]

Two questions:
1. I've started to use the Micro BR as an mp3 player (even though I'm worried about the shiny surface getting scratched or otherwise dulling up) and I find that it when it loads up mp3s, it loads another copy in an unsupported format.  The mp3 folder only registers, say, 30 tracks, whereas when I'm scrolling through mp3s on the Micro BR in mp3 mode it will show 60 tracks, half of which are unsupported and copies of the first 30.  Can anyone explain this?  Is it a bad thing? Is it soaking up half of my 1gb card?

2.  Supported mp3 formats.  Some are supported and some are not.  Is it the bit rate or is it the stereo format or is it both?  I haven't been able to work this out properly.

I don't know if it is just part of the Micro BR love affair but if I take a CD and convert it to mp3 then put it on the Micro BR and on the iPod, the Micro BR sounds better.  Is this imagination or are there real reasons for this? (I suppose that was three questions, sorry.)