Strange Broadcast Overtones?

I feel I may be the only person on the planet experiencing this, but does anyone else hear faint repeating high-pitch tones in the background of home games? About two seasons ago, I thought I heard what I’d describe as a food fryer timer not being turned off or an emergency exit door being left open. As if the mics were picking it up from somewhere inside the ballpark. But then I heard it regularly. I hadn’t heard it as much this season, but now I feel it’s back. I have some tinnitus, but I perceive this differently, and my hearing exam said I have no hearing loss. I also have perfect pitch so recognize this may be part of the curse. Sometimes I mute the tv and catch the audio through my local a.m. sports radio to avoid it.