How to get ALSA to trigger events for USB audio volume changes on the hardware

I've been trying to figure this out for a while, and I've even posted a few questions from different angles on it, but I have yet to get a response. So, if my question is nonsense, please let me know. If there is something missing that would make this easier to understand, please let me know. Here is the basic problem. I've got a RaspPi 5, with a PolyCom P3200M speaker attached to it. (It is actually for conference calls, so it is mic/speaker in one.) I want to trigger events if the volume keys on the speaker itself are pressed. If I run amixer -Dsysdefault:2 sset PCM Playback 5 for example, it will indeed set the volume on the speaker hardware to that level. If I run amixer -Dsysdefault:2 events, and then issue in a separate term amixer -Dsysdefault:2 sset PCM Playback 5, the events are indeed captured. However, if, instead, I push the volume buttons on the speaker, the volume on the speaker will change, but no event is triggered for amixer to react to. Can this be done? Can I trigger an event on amixer events when I push the volume buttons on the speaker? Is there another way to get to the same end point of knowing when the buttons are pressed?