I have the same issue. This is the support ticket I put in with a list of all the stuff I tried, but never got a reply:
When trying to connect to google voice it loads for a few minutes then says "service not configured".
The power light and the internet light are green on the obi box.
The test call phone number works.
My google voice account is fully set up and logged in with it's own number.
I can make calls from my computer using my google phone number.
I've logged out of everything and relogged in.
I've unplugged and replugged in the obi.
I've deleted the device, and re-setup everything from the add device page.
I've done the entire reset start to finish from this link:
https://www.obitalk.com/forum/index.php?topic=13868.msg89076#msg89076