I'm trying to fix a issue where calls on FXO ports on a 1760 have really low volume where the user on IP Phone can barely hear the caller.
The IOS was early 12.3T code, and I updated it to 12.4(16) a few week ago to try to resolve this after trying everything with the phone lines and voice-port settings and nothing seems to help.
The THL tone sweep test command fails to complete on these lines, saids ERL is to low and stops running.
I have put input gain 15 on the voice-ports and shut/no shut the ports and that does not even help the volume of the calls.
I have tried every impedance setting, and several combinations of input and output attenuation settings and nothing helps.
We had the provider out several times to look at the analog lines coming in and they do not see any problems with the lines. We sent a tech out with a regular phone and had them put it on the phone line and we called it and they could barely hear us with a regular phone plugged into the line from the Dmarc point. The line wasn't even plugged into the router at this point.
They had the telco come back out after above, and they can not find any problems with the line and say it is the customers equipment.
Is it worth trying to replace the FXO module? The problem seems to be with the lines but this is a remote site and the telco techs that have come out so far have not found any problems and I'm running out of ideas to fix this.
It is a 4 port FXO module.
Thanks for any ideas, Erick