This may sound hokie but it works!!! We use one cd player with a non ASCAP or BMI cd and feed the audio to all three of our switch sites over our T-1 network.... we have a (and I'm not braggin') Radio Shack mini speaker amplifier with a wall (wort to power it)at each location feeding music on hold. The beauty of this setup is: seperate level control for each switch, common music source for all, could act as an ac power fail conformation if your suspicious of a possible switch room power failure, just call a station on the switch and have 'em put you on hold (digital) or hook flash (analog) and you'll know!!!