[Serusers] SER & Mediaproxy: XLite - Audio OK, Sipura - No audio

[Cameron Beattie]

I am using the onsip ser.cfg for mediaproxy. All seems OK when I call 
between two X-Lite clients. However calls between X-Lite and a Sipura 2000 
have no audio in either direction. Both the X-Lite clients and the Sipura 
are on the same network behind NAT and going out to the SER/Mediaproxy 
server which has a public IP. SER and Mediaproxy are on the same server.

I've tested SJPhone to Sipura and there's no audio also, so it seems like a 
Sipura issue.

I've set NAT mapping enable and NAT Keep Alive enable to yes on the Sipura.

What am I missing?

Regards

Cameron