We're getting into remote meetings where there's one speaker (by this I mean the person speaking) and everyone else listening. The speaker can get quite loud and I hear overload distortion in the present setup, which is simply the speakerphone of an AVAYA 1408 desk telephone.

It's been years since I mucked about with interconnection of phone lines and phones, but it seems like it would help quite a bit if I replaced whatever the hell the phone has for a mic with a broadcast quality mic, and did whatever was necessary to inject its signal into the phone. I'd need to be able to trim the volume (I can easily add a volume control to an analog audio path), and I'd also use a compressor to keep the LOUD parts from distorting.

Do you know of an interface made for this?

I may have dial tone in the room; I haven't checked for that yet. The house wiring at the location is some thirty years old, probably 25 pair... I just haven't looked into it. Since lockdown started, I've only been able to get to the site once, and that was for other issues.

Thanks for any info you can share.