LMS Needs Reinstall Each Time It is Played on Duet

> I uploaded the file to you. My system has two Duet receivers, each
> attached to a separate Denon AVR in separate rooms. One is attached to a
> Denon AVR 3313ci. An ethernet cable runs from my 2021 iMac to this part

And that's the Mac where LMS is living?

You said "LMS plays a selected song for only a few seconds": does it
actually play music, then goes silent? Or are these few seconds just the
progressbar moving a little?

I see quite a few "operation not permitted" messages in the log file,
when LMS tries to read audio files. From the path I guess they're on an
external disk. Did you grant LMS, perl5.18 etc. full disk access, as
outlined in other macOS related threads?