For the posted screenshots I removed the usb audio interface to avoid the usual discussion if this is the reason for the malfunktion of SP 4.5.
I use different models of Behringer U-Phoria smaller or larger, with or withoud MIDI plugs. The quality is good for professional recording and the price “cheap” compared to other products with a “better name”. Check it with the spectrum analyzer of audacity (free and open source). Powered via USB makes to work with much easier.
To my regret I cannot use it with my Raspberry 400, the one with Raspberry 4 built into the keyboard. It will get a power-hickup with the additional power consumer. The “small” Behringers do not have any other power plug than the usb, the big ones with a couple of mike/instrument inputs etc. do. Same with the usb mixer/audio interfaces.
I did not try with the “common” Raspberry pi 4, but as you write it will work - or do your interfaces need a separate power supply.
SP obviously was and is centered on the ARM chips. I have not tried to install on 32 bit.
The Linux sound system indeed is very messy. Hopefully pipewire will smooth it out. I have installed latest Debian and found even SP 3.2.2 from repository not running/starting. Stopped it and installed Ubuntu 20.04.6 for further testing. May be Ubuntu has a broader user community?
Thanks for the hint: “The script controlling the audio output is daemon.rb which is in the app/server/ruby/bin folder This tries to connect but expects to find Supercollider sources rather than scsynth. See the function run_post_start_commands around line 1277”. May be I will check it if I find the time.
Thanks anyway, happy easter, regards
B. Bloechl