Thanks for the tips, everyone.
@snackmaster , you nailed it! The power cable that came with it was tight and wonky, and causing the issue with it losing power if barely touched. I tried another power cable and that issue is completely resolved. Thanks!
The buzzing when plugged in and powered off remains, but I'm also very sensitive to these types of sounds. I'm also using a smart plug (tried it directly into the wall w/o the smart plug, and the buzzing remains), and turn it off there when not using it, so I don't mind the buzzing.