Unfortunately, I can be rather impatient. As such, I occasionally pull the key out of the ignition a little too fast (to which this post will explain the too). When this happens, there is a weird and ever-so-faint noise which sounds like a vibration. I used to think it was outside noise, but then I noticed that, if I reinsert the key and turn until the electrics come on (not the engine - apologies for the advanced technical language), it'll stop.
Does anyone know what this is? Is there a fault with my car or am I just being too impatient and not giving the car enough time to switch everything off? Thanks!
Car: Volkswagen Golf TDi (mk5).