Got an 85 S15. Installed a head unit and speakers several months ago and they’ve been working fine until about a week ago. Seems to be a bad ground. Speakers are weak and sometimes buzzy and headunit dims in and out with the music. I’ve checked the ground next to parking break release but I didn’t know if there’s another ground I should be checking? Or something else common possibly? Wipers tend to go on by themselves too every once in a while not sure if it’s related?