Legacy GPU owner here (Asus DirectCU II R9 290) which still serves me quite well. I still take advantage of any new drivers despite there probably being little or no advantages for my card.
I'm not sure if this has happened since the last driver update or not, but when I run audio through my display port connection, any videos, whether VLC or YouTube, will start with 2 seconds of audio, then 2 seconds of mute, then audio resumes normally for the rest of the video. Also if I pause the video, wait say 10 seconds then un-pause it, the issue occurs again. I would assume something is initialising, but I'm not sure why.
I have two other sources of audio (3 in total) on my PC for various purposes, which includes an onboard Realtek HD chip and Corsair Void USB headphones and neither of these sources have this issue.
Is anybody experiencing something similar to this?