holy crap, I'm so glad I found this thread. My car started doing the same thing, and my girlfriend called me out on it :/. I seriously thought it was something more serious, but I'll poke around back there with the tips you all shared and report back with results. I love this forum!!
2011 E90--SSII--6MT--ZCV--ZP2--ZCW--2MT--Various other options--All Mine.