I've been having this problem for several months now, and it seems specific to Google Voice. The
obitalk.com dashboard shows that I'm connected to Google Voice, and if I login to the Obi200 the SP1 service status shows that it's connected, but if I try to make an outgoing call I either get the "no response from service provider" recording or simply long silence. Rebooting the Obi200 restores service so I can make calls, but goes inactive after about 5 minutes. Fortunately, once I start a call it doesn't drop, even if I talk for an extended time.
My theory is that there is a problem with keepalive communications, but I have not idea what to do about it. I've fooled around with the keepalive settings with no luck.
I have a second Obi device connected to the same router that I'm using
simonics.com sip to Google Voice and it works fine. Unfortunately connecting my second line through
simonics.com isn't an option because they aren't accepting new signups right now.
I've pretty much given up trying to fix it because Google Voice will become an entirely new service come Monday morning (June 18, 2018), so I'll just have to put up with the problem until then.