Mac Mini: No sound (on youtube & iTunes song stays at 0.00). System preferences > sound: output shows "home theater" and there is NOTHING under input including no "internal speakers".

Mac Mini: Mac OS Mojave: 10.14.1 (late 2014, 16GB RAM)

I'm getting no sound now. Under system preferences > sound output shows "home theater" and input shows nothing.

Have streaming service DirectvNow and have been having trouble with sound at times. Often a restart or shut down would fix the issue. After trying a few fixes found on the internet (PRAM reset, etc.), including going back a few days in Time Machine, I now have no sound at all.

As a double whammy, iTunes (12.9.0.164) no longer plays. Can navigate around iTunes, no issues there, but click play and the time remains at 0.00. As a triple whammy, I can no longer get DirectvNow video to play nor video to play on iTunes.

Obviously, one of the "fixes" I tried just caused more issues (I've had zero issues with this mac mini for almost 4 years). I'm guessing some subtle change in one of the updates is involved but I'm hoping for something simple as a fix.