I have two voice gateway 2811 and 2911, I have only one E1 line.
When I am connecting E1 line on 2811 router we are not facing any issue, But when we connect that E1 line on 2911 router we are facing one way voice.Last week we upgrade the latest IOS on 2911 . The telecom service provider reset the e1 from there.
Not all the calls we are facing, Some calls are facing one way voice.
Attached the debug file.