I have an IP Telephony system running in my office. I have some 7970s, 7960, 7941s, 7912s, 7905s and 7911s. All PSTN calls are loud and clear on all Phone models except on the 7911. Is this a default problem or is there something I've not configured? Please I need help.
This is what I feared. The 7.2.x release of firmware was one of the Buggiest (is that a real word?) ever. You should upgarde the phone firmware to the one listed below;
Here is the method to load the files.
Cisco IP Unified Phone Model 7911G and 7906G Installation Instructions
Perform the following procedure:
Click the following URL: http://www.cisco.com/cgi-bin/tablebuild.pl/ip-7900ser
Download the file that is listed to your hard drive.
If using the .exe;
When Using Cisco Unified CallManager earlier than Release 5.0
Login to the console of the Cisco Unified CallManager Server where you downloaded the installer.
Note the location where you saved the downloaded file.
Double-click the file to start the installation.
In the Welcome window, click Next.
In the License Agreement window, click Yes.
If a Read Only File Detected window pops up, click Yes.
After the installation finishes, click OK.
Reset all corresponding devices.
Cisco IP Unified Phone Model 7911G and 7906G Alternate Firmware format
The Cisco IP Unified Phone Model 7911G and 7906G Firmware version 8.3(3)SR2 is also supplied in a zip file, as an alternative in case a Cisco Unified CallManager is not available to run the executable installer program. The name of this file is cmterm-7911_7906-sccp.8-3-3SR2.zip.
After unzipping the firmware files, they should be manually copied to the appropriate directory on the TFTP server.
Hope this helps!