I have been experimenting with interoperability. I don't think now there is anything I can do to improve interoperatbility with Edge, and I send this email because it might be useful to someone else.
I am using Microsoft Edge 41.16299.248.0 Microsoft EdgeHTML 16.16299.
What I have found is that there seems to be a limit to the number of SSRCs that can be handled for audio and video. I was using a number of SSRCs, but have reduced this. (for edge, it is OK for Chrome and Firefox).
What seems to happen is that when the Browser analyses the SDP it basically ignores the ssrcs after the first n (I think n is 1 for video and 1 for audio, but it may be more).
There is an additional problem on my development machine which is that the browser does not make a noise. I think that is because it is sending the audio to the wrong output driver. I have a number of output drivers.
I have put a spectrum analyser into the web page which analyses the sound. I can tell, therefore, that the right sound stream is being handled by the browser, but it fails to successfully make a noise. I know what the spectrum analysis should look like for the audio that is being sent.
I also get this error:
JVB 2018-04-04 10:05:09.260 INFO:  org.jitsi.impl.neomedia.transform.rtcp.StatisticsEngine.log() Failed to analyze an incoming RTCP packet for the purposes of statistics.
net.sf.fmj.media.rtp.util.BadFormatException: inlength != 28 + 24 * firstbyte
That error does not seem to have any effect otherwise.
I also have a problem that after a bit of time Edge does not appear to properly connect to the bridge at all. It establishes some sort of ICE connection, but nothing else happens.
I think these are all microsoft bugs that will need to be sorted by microsoft. However, I thought my research on the issues might be of use to someone else.