Cross-post: I just tried the latest release of Plex Media Server (1.22.1.4228) on my Windows machine, and I am still getting the same issues. Here are some screenshots demonstrating this ongoing issue for your viewing pleasure (or viewing annoyance?). All heck breaks loose as soon as I enable the option “Use hardware-accelerated video encoding.” CPU usage drops and my integrated GPU engages as expected on my Ryzen 7 PRO 4750G, but this confounded pixel distortion begins to wreak its havoc on all my media when transcoding occurs. Now, I’m sure we’ve all heard of both Gandalf the Grey and Gandalf the White, but have you ever been introduced to Gandalf the Blue or Gandalf the Yellow 
?
Gandalf the Blue
Gandalf the Yellow
One Does Not Simply Encode With Pixel Distortion
Arwen Is NOT Impressed
The RX 5000 series GPUs have been around for almost two whole years now and all the latest generation AMD GPUs and APUs released since 2019 still are plagued by this very same issue. I realize development can add maybe a year delay to implement things, but even then Handbrake had this issue within ffmpeg resolved well under a year’s time and that is FREE software. We are now nearing the TWO -year mark for the RX 5700’s release (July 2019), which uses the same updated derivative of Video Core Next that the Ryzen 4000G series APUs like my 4750G has. And yet, with almost two years down, there is still no fix in sight for Windows users. It’s downright disgraceful to be quite honest.
