Cucm 11.1 background noise on 8841

[Simke-360]

I have voice quality issue with my new deployment Using 8841 endpoints and  running latest firmware sip88xx.11-0-1-11. It seems that there is a lot of background noise it sounds like humming noise on max volume, It is not noticeable at half volume.

I already bypass all layer one infrastructure connected phone directly to switch, switch to voice gateway to isp fiber circuit still same issue, it seems that call manager is producing the noise it does it IP Phone to IP Phone.

I have set dial-peers to no vad and vad its disabled on call manager.

I appreciate your help.

Thanks,

[Adarsh Chauhan]

Hi,

do you have any other phone model to test this and isolate it if its a phone issue or not.

Also what makes you say that its call manager producing the noise?

call manager shouldn't be in the picture when the call is established between endpoints unless a media resource is coming in picture.

Please rate and mark if helpful

Regards,

Adarsh Chauhan

[Simke-360]

Yeah I was thinking about media resource. I only have one 8851 and rest of them are 8841.

For some reason call manager is forcing phones to negotiate g711 even though I have  advertise g722 enabled. 

I created new region put only two phones in it but you can hear the noise as soon as you get dial tone and start dialing. I even tried 11.5 firmware for the phone still didn't help.

I took captures from call manager and with Wireshark all the rtp stream seem fine.

Thanks for your replay,

[Adarsh Chauhan]

Hi,

so to make things simple.

can we plug in 8851 and 8841 to one switch and let them be in same device pool.

Now we make call from 8851 to 8841 taking pcap from the back of the these phones (separately but simultaneously).

Now what is your observation?

Please rate and mark correct if helpful

Regards,

Adarsh Chauhan