I was getting this same problem (and resolution) for quite a while.
A couple of days ago, however, when my internet connection dropped, the problem reappeared and now the standard resolution no longer works.
I tried resetting my google voice account information and also tried unplugging the OBI100's power cable. I used the reset button a couple of times as well. None of these approaches yielded anything promising.
The power LED is solid green, the internet flickers once in a while (***1 says it has an IP address, so that's working), but the phone LED is off and the status on the dashboard id "Offline". On OBI startup, the phone LED eventually flashes twice and then looks solid, but only for about a second or two before it turns off for good.
Any ideas? Help would be appreciated!
Thanks!