Just wanted to pop in here and say thaks to the topic creator. I had the same issue "randomly wake up and generate some mad popping sounds" . Openned my device and start testing caps. Lo and behold I had the same failed caps mentioned by enduser:

C4,9 22uF/25v 20% - CapXon - open
C12 330uF/16V 20% - Su'scon - open
C37 47uF/16v 20% - LASTING - out of tolerance

Tested some other caps. They where ok. Changed the big filther caps(3300uF) just in case. After the test assembly i'ts been 48 hrs. and no random switch on.

So this tread is a live/money...