MS Lync Server - I need to hold and unhold calls before the recipient can hear me :'(

[Ric_]

Lync is awesome and I've nearly got everything the way I want it but I have hit a stumbling block.

Using the Test-CsPstnOutboundCall cmdlet, everything seems fine. Testing an outbound call from either Lync or a Snom 300 handset hits a snag though. The Lync user initiating the call can hear everything in all its HD glory but the remote party cannot hear the Lync user.

By placing the call on hold and then taking it off hold, the problem vanishes. DTMF tones generated by button presses can also be heard... it just seems to be the voice audio.

The setup is a single Lync Standard Edition server with Mediation Server co-located using a VegaStream Vega 50 Europa media gateway to connect to an ISDN-2e line.

[Domino]

Use wireshark to capture the traffic while you're placing the call.

obviously somethings going wrong that gets negotiated later - maybe a codec mismatch with the gateway?

[Ric_]

Use wireshark to capture the traffic while you're placing the call.

obviously somethings going wrong that gets negotiated later - maybe a codec mismatch with the gateway?

Watching the gateway logs (live) there is no renegotiation of codecs.

I have also tried every permiatation of the three trunk settings.... 'enable media bypass', 'centralized media processing' and 'enable refer support'.

Should I be traffic capturing bewteen the client and server or the server and the gateway? Or should I just find a fine adjusting tool?

[Domino]

I'd start with client -> server

If there's no renegotiation of codecs maybe lync is reporting to be talking one when its actually another? or a subset? Can you force a codec on the gateway?

[Ric_]

Can you force a codec on the gateway?

I believe so... it is currently using g711Ulaw64k after first trying g711Alaw64k.

[Ric_]

It gets better... playing with codec nonsense has broken it further!

[Domino]

If you wireshark the client -> server traffic can you pull the voip audio?

If you can hear both sides of the convo in that it might tell you where the call issue lies

[Ric_]

I have wiresharked the connection and can see data passing between the client and server when a call is initiated. This is what I would have expected since internal calls work :-/

Time for more Wiresharking I think

[Ric_]

Well I've now unbroken it enough to get it back to how it was before... single-sided conversation until you hold/unhold

[Ric_]

My Wireshark trace didn't show anything up and traffic between the parties looked fine.

Surely somebody knows something about OCS/Lync?