I currently use the Obi110 as my primary VOIP. Its on SP1. My issue is that it seems a little laggy. I can't carry on a conversation without interrupting someone or them interrupting me because there seems to be a long pause. Never had issues with other Voip services. Is this just a google voice issue? I have the Obi DMZ'd in the router.
My experience is there is some delay inherent in Google Voice regardless of the method of access. Additional delays could be caused by latency within your Internet connection. Monitor the round trip time for a whle using ping to see if it's excessive (>100ms):
C:\>ping /t 74.125.157.125
Ping statistics for 74.125.157.125:
Packets: Sent = 160, Received = 160, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 33ms, Maximum = 73ms, Average = 34ms
It doesn't look like latency is the problem.