Why is one of my AirPods louder than the other?

I've recently had issues with my airpods playing louder in one ear than the other. I immediately went to adjust the headphone balance in settings, but quickly noticed that I couldn't get it to stay fixed. The balance would seem fine, and then be off again in the next song. I quickly noticed that it wasn't just the general balance, but specific sounds that played far louder on one side than the other. The sounds that seem to be affected are lower tones and percussion instruments. Strangely enough, I'm having this exact same issue with my apple wired headphones as well.

I've tried everything I can think of/find: I put the earbuds in opposite ears to see if it was my hearing or the way it sat in my ear. But I still heard the base-y sounds far stronger in the same earbud. I tried Cleaning the earbuds, and cleaning my ear. Even if I set the earbuds to stereo mode (which is not something I plan to use anyway, the audio is still unbalanced.)

I have absolutely no idea what could be causing this issue, or how to fix it, but I'm not sure if I'll be able to listen to music on my mac or iphone until I find a solution.

[Re-Titled by Moderator]