Bad audio quality 9608 with G450 - Low volume, muffled

[alcaya69]

Hello,

Sorry for my bad english, I'm french and junior technician Avaya.
I have a problem with audio quality on many post 9608 on many remote sites.
The sound is muffled and the voice level is low.

All phones use the same network region, and outgoing calls use 4 trunk on G450.

The gateway G450 and ip phone firmware is up to date
(release January 2013)

My environment is:

CM 6.2 (SP2)
ip-codec-set are G729A / 40 ms (G729A with other NR)
The Digital Loss Group is set to : 13

The support network is MPLS and the quality of service is configured to DSCP 46.

I'have installed Prognosis to check the latency and Mos, all is good for me (jitter >5ms, pkloos >2 %)

Do you have issue to resolve my problem?

Thank you.
FA

 

[dialtonebone]

Try doing a list trace station XXXX on a call between sites and post the results. Note if there is any latency or jitter there. Not that Prognosis isn't to be trusted, but it's nice to have some raw data.

 

[alcaya69]

Hello everyone,

Sorry for my late reply. I come to you because even support Avaya can not find solution to my problem ..!.

Despite changes in the group Loss (location-parameter), deactivation the AGC (AGCHAND 0), adding parameters AUDIOENV in 46XXXsetting., I still have not found a solution to my problem of audio quality on 9608.

Users complain that the sound is too muffled, and he did not understand the speakers (often are numbers and letters).
The sound is very low.

The problem arises when calls pass through the mpls Wan (G729A 40 ms).
QOS is in place via the DSCP tag 46, and set at 150 kbps for two employees per site. (Commercial agency)

Trunk ===> MPLS ===> IP Phone 9608

I also checked the timing of DS1.
I have no problem when the calls remain on the local site (G711 Alaw).

Thank you for your help.

PS: I speak very little English, sorry for the translation