How to get mp3 playback?

[chigga]

hi all i'm sure this is covered somewhere but i can't seem to find it, anyways.. here we go... i have a 2000 4.4i X5 with 6 disc Cd changer with DSP and NAV, is it as simple as just upgrading the disc changer to get mp3 playback? or is there that needs to be done? Currently it does play burnt cd's such as cd-r/cd-rw copies but once i throw mp3 files on there it does nothing.

Any help is much appreciated, i'm getting the mod bug and have ordered about $1K in accessories just this week.... i want to keep it rolling so i can feed this itch! Thanks guys!