Just a quick FYI -- this evening while working on 3 different videos I noticed skin tones looked very blue.
I inspected the source files playing in VLC and Media Player and the skin tones were, in fact, perfectly fine in other apps. But they were blue in Vegas 20's preview, as well as a video I rendered (using a Magix AVC/AMD codec).
Noting I had updated my AMD video card driver about 30 minutes earlier, I rolled back the driver version and the problem resolved.
Just wanted to post this experience here in case anyone else updates their AMD driver and suddenly has a similar problem...