I have an OBi200 at my office registered under my acct. Placed another OBi200 in our main office with an OBiLine registered under my boss. Added each user to other users "Circle of Trust". Added the OBiLine to my speed dial as 2. When I dial 2*xxx-yyy-zzzz , I get to dial out from main office OBi200 on OBiLine. About 1 minute into the call, I get a tone on the line and it dosen't go away. Please advise.