My R-41PM speakers are connected to my Macbook Pro 16" running macOS 10.15.7 via USB. It seems that the speakers are somehow sending the Mac a constant volume down signal when connected. This manifests itself when attempting to reduce the volume using the keyboard buttons, where the volume jumps down several notches per keypress. I've uploaded a video to YouTube that demonstrates this. In the first part of the video, where I press the volume down key 3 times, which reduces the volume all the way to muted (instead of 3 notches). I've tested & confirmed this issue on a brand new M1 Macbook Air running macOS 11.2 - however, I was not able to reproduce it when connected to a Windows PC. In the second part of the video, I'm using BetterTouchTool to attempt to record a keyboard shortcut. As soon as I focus the input box to record a shortcut, it detects that "volume down" is being pressed, even though I don't have any keys pressed. Both of these behaviors stop when I disconnect the speakers.