Chosen Solution
So my speaker when it’s projecting “normally” it sounds like the screen is shaking like if it’s super loud but does it when it’s even half way. Also, though about a week before writing this if I had the speaker to my ear like if I was really trying to hear something clearly, it would change to being really quite like if the speaker was reversed and trying to project in the phone or something and also does it if I have my phone on the counter while I’m showering and it’s super steamy.
Seems like a failing speaker. Did the phone by chance get wet? Have you tried a hard reset? Worst case scenario you will need it replaced, or to back up all of your data and factory reset. If you have Apple Care or insurance you should check with them before having it repaired 3rd party.