Call Quality Issue

[Yort Mantup]

Hello,

Looking for some help.  We have a site that stresses it's data circuit daily and consistently.  We have QoS in place.  They have a local PRI.  It just came to my attention that there are intermittent call quality issues (robotic sound, choppy, cutting in out) when they are dialing into our Lync conferencing solution.  There are no reports of inbound and outbound calling issues that do NOT terminate back here to our VOIP or Lync systems.

Our VOIP is centralized here at our two data centers. 

I set up my phones CSS and location to dial out of that site and tested.  Able to duplicate the issue and is intermittent. Also experienced the issue when calling into a call hander and UCCX.  All makes sense based on data interface utilization. 

I am assuming QoS does not apply to calls that go out PSTN and terminate to a Unity Call Hander, UCCX or Lync? If so, is there something I can look at or change to help alleviate the call quality issues.

Codec used for all sites is G711.. thought about changing the site with the issue to G729.

Site uses MTP from their local router.

CUCM 10.5 (1PUB 1SUB)

Thanks!

[m.batts]

First of all you need to see if it is a QOS issue.Normally I place a call from the selected phone and use "span to pc port".I then run wireshark on the PC and look to see if the incoming RTP stream has EF marked.

By the sound of it though you do have a QOS issue.Are you using a qos trust model?