They already do audio watermarking like this and it can be annoyingly audible, it sounds kind of like a warbling or volume variation noticeable on sustained not

They already do audio watermarking like this and it can be annoyingly audible, it sounds kind of like a warbling or volume variation noticeable on sustained notes. At first I thought it was Youtube compression and then I started noticing the same thing in other streaming services. I switched to listening through subscription services offering HD audio which is watermarked differently in a way I can't hear.