I have a very strange problem with a relatively new PC with Core i5-13600K @3.90GHz. At least two web browsers are playing video extremely slow (1-2 FPS) when sound is directed to the 4K TV LG.
Mainboard is Gigabyte Z790 AORUS ELITE, without additional graphics card or anything else, except RAM, CPU, Samsung SSD in NVMe slot. Mainboard have only one HDMI and one DP, so I cannot try a second HDMI output.
PC have two displays - a 4K DELL monitor connected to the DisplayPort and a 4K LG TV.
The LG TV works fine with a previous, older, PC, and some notebooks. Any other PC I've tested didn't show the same problem as new one has.
The problem manifest itself in Google Chrome and Firefox (I didn't test Edge) - at least one last update didn't help.
Operating System is the current version of Windows 11 Pro (fresh installation).
I tried to update drivers for both displays and Intel UHD Graphics 770 - didn't help. Windows didn't found newer driver, only reinstalled the already existing.
Interestingly - VLC player works without problems, doesn't matter when the sound is directed to the 4K TV trough HDMI or trough analog LINE OUT. There's no difference.
Video playback in web browsers works fine when sound is directed to the analog LINE OUT.
I tried disabling hardware acceleration and DRM in Firefox - no influence.
I tested it on two different services - YouTube and Dropbox - video lags on both of them every time sound is directed trough HDMI to the 4K LG.
So, what else can I try? Is it a bug in Intel Graphics driver? Where else can the problem be?
