OP - can you unplug the active sound module to rule that out? Its a 5-minute process described in one of the DIY posts here:
http://f10.m5post.com/forums/showthread.php?t=983411. Post # 63 states to remove 3 fasteners rather than all of them - the 3 are all on the left side of the trunk, with 1 of the 3 just underneath the lid opening - so you don't have to remove all fasteners and panels.
For the DCT whine, on my 2013 it was a lot more prominent than my 2015. Used to hear it daily, and now I can't say when the last time I've heard it was.