[Jackaudio] Help with blocked USB keyboard devices on RPi 4B

Hi there, I'm a bit frustrated, because I am setting up a sound installation out of reach, and need a remote shutdown key. I had a Logitech R400 presenter lying around, so I tried that. It works fine on my laptop (Debian 12), using KeyState UGen in SuperCollider. But on th RPi 4B (Raspbian 11, for reasons) as soon as jackd is started, the keyboard input is blocked and doesn't register. I first thought, it might be that the Logitech uses bluetooth or something similar, so I got a Flirc USB dongle. The same behaviour: works fine on the desktop, but on the Pi, as soon as jackd starts, input is no longer received. If I kill jackd, keyboard input comes back immediately. I tried to use different USB ports, makes no difference. The audio device in a trusty Logilink UA0099 class compliant USB interface. (To reiterate, using this same setup on my laptop has no issues). Any help is appreciated. Best, .h.h.