Intermittent speaker and tweeter buzz, driver door
 

Hello everybody
(2000 Em1, EX, D16y8)
About 6 months ago I installed a touchscreen stereo headunit with a built in amp 50watt RMS per channel, with 4 channels.
within the last two days, I've been getting an intermittent buzzing noise from the driver door. At first I thought it was the vent or something, but I put my ear to the tweeter and it was loud and clear.

the pattern is about 10 seconds of loud buzz, then 20 seconds off. And it repeats this consistently, although there are sometimes when the frequency of buzz changes a little bit.
I discovered:
-the car does not need to be running
- the stereo needs to have some volume, if it is muted there is no noise, but past 1 volume click the buzz is no longer affected by stereo volume.
-no aux cord is plugged in
-no phone charger in plugged in

now for the weird part, today it was driving me crazy so I took my door panel off, and unplugged the tweeter, and the buzz noise moved from there into the main door speaker. Then I unplugged the main door speaker and it appeared in the right side main door speaker!! I feel like I could chase it through the entire car

additional info:
I usually have a steady scratchy sound through all my speakers that behaves the same way but that's ignoranble because it's consistent and relatively quiet, and the same in all speakers.

please help its super annoying! I cannot listen to music without ripping my hair out!!! Thank you

it sounds like you have some distortion emitting Front the deck. Have you ever turned up any of the output settings?