How does one implement such thing? I need to adjust the sound according to the speed of the vehicle. Can I work with wav files or is there another way? Thanks :)

Hmmm, that's a tough one. MMAPI does have an interface called PitchControl that can help you control the pitch of a Player (you access this interface using Player.getControl()). The big problem is that MMAPI implementations are sooooooo flaky on the actual phones that I'm willing to bet that it just won't work/sound right on 90% of the phones you try. (DISCLAIMER: I've never actually tried using a PitchControl).

shmoove