IP phones unregister and register back (reset) intermittently if the cable connected to the PC port of the phone on the PC port is unplugged

[TCC_2]

Core Issue

The IP phone unregisters and registers back (resets) when these events occur:

• When the cable connected to the PC port of the phone is unplugged.
• When the PC connected to the PC port of the IP phone is restarted or booted up. Basically, any kind of link flapping on the PC port can cause the phone to reset.

Resolution

This problem is documented in Cisco bug ID CSCed52164.

Note: This problem is not observed with the Cisco IP Phone 7970 models.

This problem is fixed in Cisco IP Phone load 6.0(3), which can be downloaded from Software Download: Cisco IP Phone FW 7900 Series (NON SIP).