How to prevent PlexAmp from auto-downloading and upgrading?

Hi.

I’ve run PlexAmp 4.12.3 on an older MacBook Pro with MacOS 10.15.8. How do I prevent PlexAmp from automatically downloading the latest version and upgrading? The upgrade does not run on my system.

My current solution is to never quit PlexAmp and never restart the computer. If I have to do so, I keep a spare copy of the .dmg file handy and reinstall the old version of PlexAmp. Fundamentally, I do not like software automatically upgrading/installing itself without my permission.