Nortel IP Phone Users "sound quiet" to externals

[Malcybood]

We have a really strange problem with our IP handsets at certain sites - intermittently.

We run succession CS 1000T/E v4.5 and use phase 2 Nortel i2002, i2004, 1140e, 1120e IP handsets.

At 3 of our sites we have had complaints where our people "sound quiet" or are asked to "speak up" when on a call to an external traversing the Media Gateway cards onto the PSTN.

We have tried all of the obvious things like handset volume etc, checked QoS settings are OK / enough bandwidth reserved for voice traffic, Correct codecs being uses (G729 for WAN locations and G.711 in the data centre).

Has anybody else experienced this issue or can advise of anything to tweak on the succession etc? It's completely intermittent and we've found no common denominators between the sites other than they experience the issue!!

There are no issues regarding poor speech quality, clicking, sounding like a dalek ONLY sounding quiet to externals but our users can hear them fine. Also there are never any issues calling internally within the company, isolated to external calls.

3 Sites out of 24 have reported it and it is specific to certain users. All remote sites run on 2 or 4 mbps ATM/Frame Relay access into a service provider MPLS cloud with COS reserved for voice traffic.

We are trying to build up a trend analysis but having little joy getting the users to record the info, so its a difficult one to troubleshoot at the moment!

Any input would be appreciated.

Cheers
Malc

 

[Bottylad]

Did you resolve this?

I have a similar problem where calls into our call centre (1150 users) sound 'muffled' to the external person. The 1150 users reports no defect. These calls come in from another CS1000 via a data link to a 1000B - which is then linked to our CS1000 via DPNSS (I know this sounds tenuous).

I have tried adjusting the PAD table 15 PRI/PRI2 values but this doesn't solve the peoblem, nor does adjusting the loss plan of the Sig Severs The volume levels are fine in actual fact and there are no apparent QoS issues (crackle etc).

Internal calls desk to desk are fine and calls via the 'normal' PSTN are fine too. It just seems to be the external calls which come from a seperate CS1000 > Data > 1000B > DPNSS > CS1000.

The Codecs on my system are G711 - but the 1000B uses G729

Any thoughts?

 

[pcat200]

I have encountered users that were in a different location complaining of muffled speech and found it to be caused by the incomming calls going from H323 trunks on the originating side to IP trunks on the target site. I modified the NRS to send the calls fully on H323. Turned out the target site had both IP trunks and H323 trunks. Both endpoints were registered to the NRS.