DisplayNameJack

Hi! I've got a 2023 iMac and I plugged in a new THX system into the speaker output. Unfortunately, if the auxiliary plug twists even a fractional amount, I get crackling through the speakers. This could be caused my anything, like the vibrations from me bumping into my desk. So, I tried connecting through an auxiliary-to-USB adaptor, which worked great - until I shut down my computer. When that happens, the speakers release a continuous deluge of random static, even if I shut turn the volume all the way down (albeit, more quietly). So, my current solution is to power everything through an APC and turn that power source off, after I shut down the Mac. Is there something I'm neglecting here? Thanks!