We are using the CallManager 3.3(3) and 2611 as the voice gateway. There are 8 analog lines connected to the 8 FXO ports on the router. Some users complaint that the valume will be drop down very low even mute for a few seconds and back up on the 7960 IP phone, so they may loose some information from PSTN caller.
I upgrade the IOS to 12.2.15ZJ3, but the problem looks still there. Is there any tune solution can address this problem on voice gateway? In the meantime, i am going to apply the sr2 to the ccm server, but i am sure if it is helpful.