We have about 350-400 7961G IP phones in our network and since about a week quite some (I think at least 10 reports/day) calls don't have inbound sound: The external party does hear us, we don't hear them. This problem happens with both inbound and outbound calls.
First we thought it was a firmware issue, since the first time the problem occured (about 1.5 month ago), we figured out that if you put the call on hold and get it back, the inbound sound was working again. We were running 41sccp.8-2-2ES1 back then.
After a period of testing (which seemed to solve the problem), we upgraded to firmware 41sccp.8-3-3ES2. Two days after that the problem got worse, multiplying the number of 'broken' calls by 4 or so.
Because of this, yesterday we went back to firmware 41sccp.8-2-2ES1. But still we get as many troublesome calls as we had before. So this seems to be independant of the firmware version.
Is anyone familiar with these problems?