Duplicated files in the music library

Hi, I have this kind of annoying problem with my music library on the phone. It seems that the music player discovers many of my mp3 files twice or more, so when I browse the library in the music player program it looks like I have a lot of duplicated songs, but I am sure that I don't have! Do anyone know why this happens?
My first thought was that the music files may have more than one ID tag. Like one IDv2 and one IDv3 tag. If that's the case then how do I delete one of them, or make them all into IDv3 tags?

Right now I am using fw 0915, but I've had the problem since I bought the phone, and then I had fw 0905.

I hope you understand the problem here.
I'm sorry if there's any threads like this on the forum, but I couldn't find any.

JaffZe,
do you have 1 or more .m3u file(s) in the music folder ?

I have 8 different M3U files in my playlist folder
Some of them contains the same songs! Do you -know- if that's the issue?

The ASX playlist files that you can make with the M8, does that work fine? If so, then how can I convert M3U playlists into ASX playlists?

i don not use m8 for mp3,
but while making a test i had 1 folder with 3 miu files:
cd1.miu
cd2.miu
main_2_cd.miu

this created duplicated playlists on my device... so i removed cd1/2.miu
refreshed music folder and my issue was solved.

I hope this helps.

Thank you!
I will try it later when I get home from work.

But still, do anyone know if there are any good programs that can convert m3u files into asx? Because it's pretty weird that the M8 doesn't "want" you to have the same songs in muliple playlists
It doesn't seem like it creates duplicates when I create a new playlist with the music player on the M8, and it is asx files that it creates...