1.4 TSI engine mounts / vibrations

I've got a 2012 1.4 TSI DSG with 17300km on it. Last week, I noticed more engine vibrations than usual. Especially when reversing, when also during engine braking (manual downchange) and when lugging the engine at around 1100rpm in D. 1100 might sound low to some people, but it's where the DSG typically wants to be when left to its own devices. Also, today was the first real warm day of the year and I also noticed it when the AC compressor engaged. 

I've been out driving today and decided to finish the trip by giving it a wash. When I started it again after the wash, it was back to normal again. It was a manual wash and I'm fairly sure I didn't get a drop onto any engine electronics or anything like that, so I don't think the wash really made any difference. 

Does the 1.4 TSI have some kind of active engine mount or something that might be controlled by a vacuum valve? I can't see how a normal engine mount could "repair itself" like this. Obviously the problem could be elsewhere, but I just don't know where that could be. 

Any ideas?