We have a fairly simple setup, with 4 incoming pots lines connected to a TDM400 with 4 FXO modules. 2 of the lines are dedicated to the 2 specific users, so they can still have a direct phone number as opposed to having to use an extension. The problem is this: When they call out, or when someone calls them any additional calls to that phone number ring busy. Is there any way I can detect the incoming call and put it right to their voicemail even though the line is busy, or do I have to use some type of call busy forwarding through the phone company. This seems like it would be a fairly common problem but I can’t figure out a better way to fix it. Would moving to a T1 fix this, and if so how?
One other alternative is to get a DID (direct inward Dialing) block of numbers from our service provider and then forward the line when busy to one other phone number (that you don’t give out so shouldn’t ever be busy), but all these features cost money from our provider and we’d like to stay away from that if possible.
Any help would be greatly appreciated.