Multiple instances of AudioTrack (and streams) in one service?

Question

I have a streaming music application that can play two streams simultaneously, using two separate services using one AudioTrack each in their streams. Now I would like to play more than two streams, and I think that more services is not the way to go.

Is it possible to have one service with dynamically created AudioTracks? How can I implement separate streams for each instance of AudioTrack? How can I access dynamically created AudioTracks?