Question Weird CPU/GPU utilisation behaviour and crashing when I play a YouTube video whilst playing a game.

[LPNUK15]

Specs:
6600XT
I7-10700f
16GB 3200MHz RAM
650W Corsair PSU
B560 MOBO
Edge browser

If I launch a game with no video playing, everything is fine. Utilization is normal, frames are normal, no stuttering or anything.
However, if I launch a game with a video playing then my CPU and GPU utilisation is very low, with my CPU utilisation being below 5%. However, the temps remain similar. If I then pause the video everything crashes and I have to restart my computer, or if the video is on for too long everything crashes also.
This happens on every video, and resolution. I have not tried any other browsers however.
This is every single game I've tested. GTA V, God of War 2018, EU4, Lego Star Wars TSS.
The behaviour is consistent throughout all of them, and this behaviour is new (about a week ago it started) but I cannot think of any changes I have made to my system. No new hardware, no critical or suspicious software, nothing.
I ran a windows defender scan to see if that brought anything up but it didn't.
There are no odd background processes in task manager either.
Has anybody had this issue before? Any advice would be greatly appreciated.
I am on Windows 10 build 21H2, but the previous build had this issue also.

 

[LPNUK15]

Specs:
6600XT
I7-10700f
16GB 3200MHz RAM
650W Corsair PSU
B560 MOBO
Edge browser

If I launch a game with no video playing, everything is fine. Utilization is normal, frames are normal, no stuttering or anything.
However, if I launch a game with a video playing then my CPU and GPU utilisation is very low, with my CPU utilisation being below 5%. However, the temps remain similar. If I then pause the video everything crashes and I have to restart my computer, or if the video is on for too long everything crashes also.
This happens on every video, and resolution. I have not tried any other browsers however.
This is every single game I've tested. GTA V, God of War 2018, EU4, Lego Star Wars TSS.
The behaviour is consistent throughout all of them, and this behaviour is new (about a week ago it started) but I cannot think of any changes I have made to my system. No new hardware, no critical or suspicious software, nothing.
I ran a windows defender scan to see if that brought anything up but it didn't.
There are no odd background processes in task manager either.
Has anybody had this issue before? Any advice would be greatly appreciated.
I am on Windows 10 build 21H2, but the previous build had this issue also