Sorry Steve (bluescat?) about cross posting between the OBi and Google Voice forums.
I followed the troubleshooting recommendations at GV forum including removing OBi, leaving only web, making sure there was no GV on my cell phone/restarting.
Called the OBi/GV number from other phones (ATT MVNO, TMobile postpaid, Google Fi) and all calls go through without issue.
My Moto x4 still disconnects after 2 rings, no VM. When calling from my cell phone, using its GV number, calls fail if using "carrier" but succeeds under wifi calling.
There are no blocked numbers on my Moto x4 Tello (TMo MVNO) phone.
i have started a ticket at Tello but feel free to offer any suggestions.
While possibly unrelated, other posters suggest uninstalling (reformatting) OBi device. That might be a big hammer for a small problem??