I would like to bump this thread and ask a question because I have the same issue. My problem arises only when I’m in the menu screen of several different mods I have for my consoles as far as I can make out. I have an everdrive for n64, psio for ps1 and OPL for Playstation 2. Whenever I’m in the menus of these systems I can hear the same buzz from my TV. The different systems have different colors in the background but two are different scales of gray and one is black. I have scart cables for all of these from retro gaming cables. I don’t think I hear this when any games are on but it’s hard to tell due to the sound being lower volume than the video posted here. My OSSC is the latest revision. Any ideas?