Using the libs I sent you, you can do:
Function mciMP3Seek(ID, Position$) ; position can be "start", "end", or millisecs
Don't know if its working for wav and midi, but it should work ok (of course, replacing the function for mciWAVSeek and mciMIDISeek).
With this you can skip to any point in the song, just get current position using mciMP3Position (or mciWAV, mciMIDI...) and add/remove how many milliseconds you want to go forward or backwards.
Function mciMP3Seek(ID, Position$) ; position can be "start", "end", or millisecs
Don't know if its working for wav and midi, but it should work ok (of course, replacing the function for mciWAVSeek and mciMIDISeek).
With this you can skip to any point in the song, just get current position using mciMP3Position (or mciWAV, mciMIDI...) and add/remove how many milliseconds you want to go forward or backwards.