[SR-Users] mediaproxy-ng one-way audio (but not all the time)

Hello, I am testing mediaproxy-ng (running on CentOS 6 on Amazon EC2) for WebRTC to non-WebRTC calls and I am getting one-way audio most (but not all) of the time. I always get audio in the WebRTC to non-WebRTC direction. Has anybody had any experience of anything this? I have checked the obvious (all the ports open in iptables and the Amazon security groups). I know that the right (advertised) address is going into the SDP. I am getting an error message out of mediaproxy-ng a lot. But it is there whether the audio works or not. The error I am seeing is: "Error generating SRTP session keys". Regards, Peter -- Peter Dunkley Technical Director Crocodile RCS Ltd