[LAU] pipewire: How can I exclude a device?

Hi! I'm using Linux-Show-Player (LiSP). LiSP allows you to make use of any audio port there is with the jack-output-plugin but, unfortunately, under pipewire it just doesn't. (There seems to be a bug in gstreamer-jack.) So, I have to switch to jack, from time to time. There is a cool configuration-script in Ubuntu-Studio on my main multimedia-workstation, which allows switching from pipewire to another config where I can start jackd - and going back without any hassle. But on my laptop I'm running Debian. It's said that pipewire works great with jackd. Unfortunately, it's not self-explaining… Under Gnome - what steps do I need to take without de- and reinstalling anything… Keeping pipewire alive, but excluding a sound device, f.e. the one that I normally plug on the USB bus and then starting jackd on it. Should not be too hard, is it? Greets! Mitsch