orbit communications DA-2 specs

[Babybearjs]

if anyone can help, I got the DA-2 off of ebay for $2.00 and need the specs on this unit. its labeled "Tel Butler" and looks like a paging unit. I need to know if this unit can be interfaced in a 1A1 system as a music on hold unit. I'd like to hook it up so the music on my computer can be used.... the terminals are pretty statight forward, M1, M2 Gnd, T, R, S1, S2 and P1, and P2 (power) I'm assuming that M stands for "Mic", S for "Spkr" so if I run my audio through M1, M2 I should be able to get it to work through the system. it looks like I can add an external speaker to adjust the volume control, etc. Orbit Communications is still in business, but handle direct TV now.... if thats the same company...   any help will be appreciated.    John