I've been trolling around google and other sources and Can't find anything about it so I thought I would post my story and get an opinion.
I have a 2000 Audi A4 1.8T with a stock BOSE audio system and an RNS-D head unit.
I drove home 3 days ago, parked, no problems. I get in someone else's car and I go off to celebrate new years stuff. I got back today, i put my bags in the back and I get in my car. I've been driving an automatic home for a few hours from my friends house so I got used to it I guess so i tried to start my car forgetting to clutch so obviously it doesn't work, took a few tries to realize that this was a manual car, I realized and I clutched in and started the car. The first thing I noticed was a slight high pitched humming/whirring sound that came from what sounded like the engine. I thought nothing of it figured it was a fan or something and it was cold idk. I was driving out of my neighborhood and my trunk was ajar (this happens a lot since my sister dented the rear bumper last year, if you don't close the back hard enough it wont close) so I pulled over and closed it (left my engine on). I Pulled out drove to go pick up someone and when I got there my car was locked so I press the unlock button and nothing happens so i try again and again, i tried it both ways up and down but it would not unlock, thought it was weird but i just reached across and opened the door, didn't really think about it again, thought I was just going crazy. Was Driving and turned down my music and i heard that whirring noise that I heard when i started the car, thought it was weird and I noticed when I pressed down on the throttle the whirring would get a bit louder so I started to get really really worried thinking it was my turbo and maybe a an busted and it was overheating or something but then i turned the music all the way down and i heard my speakers making a fairly loud HMMMMMMMMMMM so I tried the door locks again and they wouldn't work so it seemed like I had an electrical problem so I pressed the power button on my stereo and all the noise stopped, and so did the high pitch whirring noise which I thought was the turbo. Locks still didn't work. Turned it on and the noises returned so I thought about it and came to the conclusion that something wasn't grounded properly or there was a capacitor that had failed somewhere in the electrical system. I get to my friends house, turn off my car get out and open the trunk and shift around the baggage (the trunk is fairly full) because I maybe considered that the bags in the back of my car could have done something because I believe the locking module with the electronics for the locking system is in the trunk by the trunk latch. I close the trunk, get back in start the car (properly) and leave the stereo off for a few minutes, I turn it on, the humming is gone and the door locks work. what????? I got home, turned off the car and the stereo (as usual) turns off like 2 seconds after the engine and I hear a quiet buzzing which Im not sure if it was always there or not, I turn just the stereo on, the engine is not on and all there is still a quiet humm that can only be heard if the engine is off.
What could my problem be! is it just something fluke that I should pretend never happened because it never will again? I'm assuming my sister didnt drive the car and do something to it haha.
TL;DR: My car made weird humming noises through my speakers and a weird whirring through my speakers when accelerating and the lock and unlock weren't working on my doors, mostly went away after turning off car and starting it again except for a very quiet hum that you can barely hear over the engine.
I would love to get an opinion on what this is and if it will happen again!
sorry for writing a book about my problem...