Totally agree about the desire to figure it out. If we can do it, that would great.
PCMU vs OPUS is a separate issue from the noise after beep.
The PCMU part is happening because even though I am using latest master, my conf is old and I don't have OPUS in my global_codec_prefs var.
However, the original problem of noise after beep in the conference happens with the latest conf using OPUS as well. Easily reproducible on vanilla config on Windows 7. Of course switching to cdquality fixed it as did switching to 12000 in the default conference profile.
Not sure I understand the remark about the ability to hear and understand everyone in the conference. I have three types of clients who all mix and match in the conference - a PSTN termination provider (with SIP connection/PCMU), SIP softphone (PCMU) and Chrome WebRTC (JsSIP). Since the non-WebRTC end points don't support OPUS, I am not sure using it will help in this case. Will it?
Also, if I do use OPUS, any advice on how I can limit the bandwidth it uses? I saw opus.conf.xml but it was not clear how to set a bandwidth limit in it. My users are all in controlled bandwidth environments, so I need to make sure a single user does not use more than 80-100 kpbs (in each direction) even if more is available at the time.