I'm not going to provide 100s of hours of burn-in though.  I only have a couple of weeks over the holidays to get this done

In addition whilst the RxMk3 was warming up, I spent most of my time listening through my new FitEar TO GO! 334 too. So possibly another variable changing there. As such, the aforementioned huge pinch of salt comment. The only exception is the last tracks where I put on my already burnt-in UM...