Problems with phone Cisco phone 7821 - phone stop working using monofone

[AlexandreOppermann]

Cisco Telephone 7821 The problem is when the call is answered on the handset nothing happens, it only works on the speakerphone. when we restart the phone the handset will resume operation.

[R0g22]

Do you happen to have a wireless/bluetooth headset connected to these phones ? Are these on CUCM or CUCME ?

[AlexandreOppermann]

I do not have a headset plugged into the phone. The phone is registered with CUCM.

[Mohammed al Baqari]

Is this for all phones or single one

[AlexandreOppermann]

only one phone with this problem

[AlexandreOppermann]

Don't solved, I need help in the problem.

[AlexandreOppermann]

Don't solved Can you help me ?

[AlexandreOppermann]

Hello guys I need help from you.

[Georgios Fotiadis]

Is firmware the same for all 7821s? Are they on the same LAN? Replace handsets with another (working) phone and see what happens. You may have to RMA the 7821.

[AlexandreOppermann]

Is firmware the same for all 7821s? Are they on the same LAN? Replace handsets with another (working) phone and see what happens. You may have to RMA the 7821.

Is firmware the same for all 7821s? Yes is the firmware:cmterm-78xx.12-0-1-11.k3.cop.sgn

Are they on the same LAN? Yes

Replace handsets with another (working) phone and see what happens.   

I already changed handset but the problem continues ie when I take the handset off the hook the connection stays on the speakerphone.

[Georgios Fotiadis]

You should RMA the IP phone.