Trixbox and Polycom 601

Hello,

I have Pro Call Center on a box and Have several issues with the Polycom sometimes/most of the time taking and incoming call from an outside T1/PRI line. If the caller calls and me enters the extention directly it just rings for a moment and hangs up on the caller. I have some Aastra 480i, 480iCT and 9112i on the same system. Only one of the Polycoms is giving me this trouble. Do you have any ideas on this. Also do we have a stickie or info on setting up the Poycoms on this forum. I did try searching here but it comes up with topics that are not related to what I am looking for. Anything programming specific to the Polycom 601 that might be of interests to a new Trixbox install/reseller?

Thanks for your time.