Pinephone speaker buzzing whenever power sent to it

[LinAdmin2]

Just recently received my pinephone (also my first phone. not sure if that was a good idea or not yet)
At first the internal speaker was not playing any sound whatsoever. I would click the test speaker button and nothing would happen. The earpiece worked fine so I didn't mind for awhile.
After I got it connected to a cellular network, I decided to open it up to see if I could see anything obviously wrong, like a fly in between the contacts or misalignment or something. My understanding of circuits is high school physics level, so this was probably stupid also.
I didn't see anything, so I closed it up again, and it magically started outputting sound.

However, now both the speaker and the earpiece buzz uncontrollably whenever they're active.
When I select each one to test, even before playing any sound it buzzes. the earpiece is better, but still noticeable.

I've already inspected it for signs of being blown, but I didn't see any obvious holes or uneven vibrating.

So, what do you guys think the problem is, and how should I fix it? Is there a better way to detect a blow?

thanks in advance

[edit]
it is actually quite bearable with the soft case on. I'm still concerned, but it's not longer a big deal.

[edit 2]

Would a high pitched whining noise have anything to do with the battery being drained?
if not then we're back to it being a problem.

You do not state what distribution you use, so I assume it is postmarketOS stored in emmc. I would suggest that you install a recent distribution of mobian on sdxc card and test sound that way.
Most probably that problem will be gone.