Playing live Music on Hold - or play from the end of a wav?

Hi - building an application so that callers enter a call queue. Whilst in the call queue callers need to be able to listen in to the currently connected caller (think TV phone in).

This is almost easy in asterisk as the current call can be recorded to a file and the file can be played as music on hold to the other callers.

The problem is that the file is played from the beginning (or whereever the last MOH playback ended). I need to be able to always play LIVE (okay delayed by a second or two is fine) from the end of the recorded audio file - or find someway to stream the recorded file so that callers ALWAYS here the file from the end - the most recent part of the file.

Any suggestions?