I have been engraving Yeti cups for a bit, with great success.  The last 2 I did; they didn't come out right at all.  I have tried multiple different settings, and they don't seem to engrave to the clean stainless surface.  It's almost like it just engraves down to a primer coat or something.  I have tried 2 different images that I set up, and text font.  Now, just for a sanity check I tried an off brand cheapo bottle that I have been using for practice, and it worked as expected.  Did Yeti change their coatings?  Or do I need more than a 10W laser now?  Or is there some setting I have completely overlooked?