Just purchased an M2 Mac Mini Pro. As soon as I booted the computer - going through initial setup, I had intermittent flickering and vertical line issues. I used the same exact AOC U2879VF 4K/60Hz monitor I've been using with my Mid-2014 MBP. It comes and goes. I haven't seen the vertical lines in 2 days since trying a different cable, but still get flickering.
Apple support escalated me on the phone to whatever the 2nd tier is (senior?) & said it's a faulty port. This may be a hassle (waiting on a call from Costco since it was an online purchase with price match). I'm hoping they will send a new one out and let me move the data I already moved this this machine. I *think* this faulty-port issue could be a red herring based on my experience and what I'm reading from many others.
I've tested this out more. I'm pretty convinced it's a syncing issue of some kind. at 60hz, I see flickering every so often. At 50hz, sometimes there's a second of a black screen. At 30hz, no flickering. I had the vertical lines, but haven't seen that in a bit. I also noted that certain website pages (like with dense text and color shades) caused the issue to trigger. Flickering happens across the whole screen. I've seen some suggest getting a USB C to HDMI, but WHY should I have to tie up a USB C port when I paid to have an HDMI?
I miss the days when Apple delivered a product that I could be excited about and have it just work. with the Mid-2014 MBP, YouTube locked up and hard-crashed all the time on Safari (complete system lock-up). Apple wouldn't admit the problem existed for at least a year and a half, but support finally reached out to discuss the issue with me (based on hundreds of reports) and fixed Safari. (I *think* it was a work-around for a hardware bug in the graphics chip.)
Incidentally, my first call on this machine was the ridiculous smooth plastic bottom. Less than 5 lb computer...wires hanging off....smooth bottom on smooth desk....as Apple likes to say, HELLO!?????