**Note: I don't see an option to audio device into ALSA settings. I went to delete my existing audio device (to try re-entering it as a fix) but there seemed to be no way to add a new one if I did; a message to add one but no button to do so. Didn't risk it.
I had been switching from PCM to DoP in these settings but SL wouldn't start. I've had no options entered for quite a while so I added one I've used before and then SL started and was recognised by LMS...no sound from speakers, though.
Tried various simpler options like -r 384000 or -p70 and all valid options allowed SL to start. Removing all options (leaving option field blank) led to SL not starting.
So I had SL starting and selectable but no sound (even from MPD or Roon and not fixable by setting vol to 100%. A complete power down and restart fixed that.
I can still repeat the problem of SL not starting by removing ALSA options.
Agent Kith; did you have ALSA options selected when trying SL? Try deleting them and see what happens. Also please check that deleting an audio device can be recovered; i.e. a button will appear to add a new one.
Cheers