lock the volume of my Shure microphone

[wgmayer0]

I’m trying to lock the volume of my Shure microphone on an arch linux system using PipeWire, but I haven’t been able to find a reliable method. My goal is to set a fixed input volume that cannot be changed accidentally by any application or system process. So far, I have tried adjusting the volume using wpctl and directly setting the default levels in WirePlumber configuration files, but the volume still changes under certain conditions, such as when the device reconnects or when new streams are created. I haven’t explored the channelmix.lock-volumes property yet, so I’m unsure if that is the proper solution, and I’m hoping to avoid trial and error with undocumented settings. Essentially, I want a configuration where the Shure mic always remains at a specific, fixed input level, with PipeWire enforcing this restriction at the device or stream level. Any guidance on WirePlumber configuration snippets, session rules, or device-level properties that can achieve a true “locked” volume for a USB or XLR-connected Shure microphone would be extremely helpful.