I suspect this is happening with me with a specific destination number - which belongs to an AT&T conference call in system.
I have two obi boxes that otherwise work fine for incoming and outgoing calls including to other AT&T conference call numbers.
If I dial 1-866-213-2185 from a Google Voice (GV) account I just hear it ring and ring until it times out. If I call from a
VOIP.ms account (on the same obi box) it answers correctly.
What is special about that number? Have they blocked GV calls to it somehow? I have tried it from two GV accounts that have different area codes. Same result.