Artifacting on FCP

I made a video for work today, and I would see these kinds of visuals popping up in it, or black/ deleted pixels when editing. I hoped they weren't part of the video itself, but they are. Is this indicative of my graphics card on the way out? 2013 iMac 27" with 32GB Ram running 15.5 on an external SSD. I just updated to 15.6.1 to see if it would help, and it has not.