not getting full duplex

[giltheissen]

Hi;
I'm brand new to Ooma and have tried a variety of different settings to improve my call quality, but I'm still getting what seems to be half duplex. I have cable with Comcast, 25mbs down and 2.5mbs and throughput is consistent. I've switched my Ooma to Modem > Ooma > Router, and that didn't help. Then, to eliminate interference from any other possibly "half duplex" devices, disconnected the output network cable to the router. So now on my test setup I only have the modem (Surfboard sb6141) > the Ooma > and my phones. Rebooted by the modem and the Ooma, but still getting half duplex.
Is there anything else I can do? I've seen some instances where switching to the "East Coast Server" seems to have helped. And wondering if that switch might be possible (don't know what server I'm currently on although I'm on the east coast of Florida) and what else I might do to improve my call quality. Prior to this I had ATT analog (not digital) and call quality was fantastic.
Any help would be appreciated

[murphy]

Are you using a speakerphone at either end of the conversation? They usually end up being half duplex to avoid feedback squealing.

[giltheissen]

No. Speakerphones are not involved.