u can try to disable the audio of the tv throught the uotput of your laptop after you have done that go to playback devices and then enable the audio device this has worked for me
I think I tried that and it still said it was going through the audio jack. In screenshots online it looks like it says HDMI next to the realtek audio title under playback devices.. so i dont know! I'll try it again though, thanks!
EDIT: After a restart, I lost video as well. I can do the reinstall of the driver and I bet it'll work but.. something is clearly wrong
I suggest that you check with Asus* to confirm that the audio drivers for the HDMI port are properly installed, then in fact, the HDMI output needs to be set as the default playback device in the Sound properties of the operating system.