My Plugable adapter cuts out (black screen) every 30-60 seconds for a few seconds, which is the same behaviour I had with another adapter before buying the more expensive (hence my assumption of better QC) plugable one. It’s connected to a very sturdy 25 foot HDMI cable. When I plug the 25 foot HDMI directly to my RX570 video card, I get perfect stable picture at 4k60 with no cut outs so the cable is not the issue, but unfortunately my RX570 has 1 HDMI 2.0 output vs. 3 DP outputs so I have to use an adapter because I need multiple outputs.
This is either a bug in the chip in the adapter or simply not enough power through the DP port to produce a clean HDMI signal or overheating. I’m running W10.