I'm trying to figure out what's happening to me and I'm not sure where to look.

For the last several years, whenever I listen to silence-filling noise (white, brown, pink, etc.) I tend to hear additional sounds. It's like having your radio tuned to a MHz that's just off a tiny bit, so you hear static but there's just a slight edge of voices or something that you can't quite make out but is definitely there. Sometimes, instead of voices, it's also patterns in the noise or various pitches.

It happens in a variety of situations, like Youtube videos, audio tracks from meditation apps and noise generators, and even devices that have no audio input or antenna and are specifically for noise as you'd find in the waiting room of a massage clinic. It even happens when it's a completely benign source like an air fan. And the sounds I hear match the volume of the source.

Do I have superpowers? A brain tumor? Am I just sensitive to imperfect wave form generation? Am I part-dog? Have I done damage to myself from listening to Metallica way too loud for too many years?

Where do I start looking into this? Does anyone have any possible explanations for what I'm experiencing that might lead me in the right direction?