Unable to answer calls and static during calls

[Efrain Berrocal]

This problem only occurs in one department at my organization.  The department has 5 IP phones (7960).

The first issue is that there is so much static during calls that they cannot hear the caller clearly.

The second issue is that they cannot answer a call.  They pick up the handset but the call isn't answered, the phone keeps ringing. Then they press the button for the line that is ringing but the call is still not answered.  Eventually the call goes to voice mail or the caller hangs up.  Also, the phone seem to lock up during a call and the light on the handset starts to flash.  Eventually the call is lost.

Both these problems occur at random times.  There's no pattern.  It's been happening for about five days now.

The only thing in common among the phones is that they are located in the same office and all have one extension in common (although each phone has other extensions on it).

The issues only seem to occur with incoming calls.  And these calls seem to always be from outside the organization.

Help!

[Marco Rojas Abarca]

Efrain,

For your first issue, please refer to the following link:

https://supportforums.cisco.com/document/101961/how-troubleshoot-voice-quality-issues-ucm-environment-bad-sound-dead-air-one-way

This will give you an idea about how to start attacking this issues from a CUCM, IP phone perspective.

About your second issue, could be either a phone issue or and end user problem. To rule out the phone as being the culprit what you can try is to perform a firmware upgrade for the phones to the latest one available in the following link:

https://software.cisco.com/download/release.html?mdfid=268437898&flowid=46197&softwareid=282074289&release=8.1(2)_SR2&relind=AVAILABLE&rellifecycle=&reltype=all

Also, please note these endpoints will become unsupported after July 22, 2015, this according to the EOL announcement, please refer to the following link for further information:

http://www.cisco.com/c/en/us/products/collateral/collaboration-endpoints/unified-ip-phone-7940g/end_of_life_notice_c51-574072.html

Regards,

Marco Rojas