We're having a wird problem with voice quality on 7925G phones.
They are reg. on a CME 7.0 and running 1.3.3 firmware and at 5Ghz.
AP is 1242( 2 of them) and 7 phones(all 7925G).
Running QOS , used the deployment guide for 7921G , WDS and eap-fast.
This setup may run fine for like a day or 2 and then suddenly 1 phone have very bad voice quality , both ways.. literary chopped to pieces.It is impossible to have a conversation..
Signal is very strong , user/phone is allmost sitting on the AP (-40'ish)
-If dialing pstn the phone have problem
-If dialing ICT phone have problem
-If dialed pstn phone have problem
-If dialed ICT phone have problem
But if dialing/ dialed another 7925G phone LOCAL no problem.
If phone is turned off and powered back on will fix the problem.. until next time this happens. (10 min to 8 hours )
And this happens with all the phones during the week.. but never all at the same time.. not yet that is :-)
im not sure the problem is the wireless network at all.. but related to the phone or the CME
Codec is g711ulaw
Any suggestions would be appreciated.
There is a known issue with CME, where RTP is being tagged as UP4 instead of UP6 as the CME uses port 2000 for both SCCP and RTP.
This would only be an issue when the RTP traverses the CME (PSTN calls, paging, etc.), so 7921/7925 to 7921/7925 or to internal wired IP phones would not be imapcted.
Yes disabling WMM would be a short-term fix for this issue, but long-term, there has to be a fix on the 7921/7925 side.
Below is the open DDTS for this issue.
Plesae contact TAC to request 188.8.131.52.3 for a fix to this problem.
CSCtc54410 7925 with voice gaps with inbound/outbound PSTN calls