1 Way voice after transfer by outside party using keyphone system

[andyap]

I have a very strange problem at one of my customer premises running cm 4.1. We were able to call everywhere no problem except 3 sites running keyphone system. When we call the outside A, A operator transfer the call to any other phone, after the transfer, we can hear them but site A people cannot hear us.

It is the same eventhough, site A is the one that call us.

the call flow ->

IPphone->h.323 GW->ISDN Pri->PSTN->site A Keyphone system.

My question is when site A transfer the call, there shouldn't be any changes on the RTP stream from the h.323 gateway to the IpPhone right???

So what actually cause this problem, can any body shed some light on this.

Thanks in advance

[beth-martin]

uncheck MTP for 711Ulaw-GW when register this H.323 GW on CM.

[andyap]

The MTP is all the while uncheck. the only option that has been check is the option below:

retry video call as audio

Wait for Far End H.245 Terminal Capability Set

Thanks for the advice

[rhugo]

uncheck the "Wait for Far End" option. Also, check and see what codec is coming across on the local AND Remote phone (if possible...I know the remote is a station on the key system, so I don't exactly know how to check that unit...) and see if it is actually coming across as a G711 and NOT a G729, which needs a transcoder, as you know...

I ran into this problem and did some manipulation with IOS transcoders through the call legs to get it to process correctly.

[andyap]

I will try to uncheck the "wait for far end".

Anyway we are reaching the remote system via PSTN not IP Wan. Therefore it is not important to know what codec it runs. The codec from my H323 gateway to call manager is running G711ulaw.

Cheers,