Hey, not sure if anyone else is still having this problem but I think I found a solution that works for me.
I've got a newish pre-built gaming PC that has had fantastic performance until a little bit ago. To stream games from the PC to one of my TVs through some random program I had to turn off the "Hardware-accelerated GPU scheduling" in Settings under System > Display > Graphics > Default Graphics Settings. I think this caused the problem for some reason. I switched this back to "ON" and restarted my computer and I haven't had the problem again (yet).
Hopefully it's as simple a solution for someone else!