I've got a new Revo STX that I've used about 6 times, and it is a little rough on the retrieve already. I can feel it slightly in the handle when I crank, but it is slightly audible as well. It just feels a bit gritty. Visually, the worm gear looks a bit dirty, could that cause what I'm feeling & hearing on the retrieve, or is it most likely in the main gear / pinion area? BTW: the reel still casts a country mile

All of my Revos came virtually dry of lubricant.  You can open it up and lube it.  Grease on the gears, a little oil on everything else.  

If that doesn't do it, return it for another, or get yourself a Patriarch.  

All of my Revos came virtually dry of lubricant. You can open it up and lube it. Grease on the gears, a little oil on everything else.

ALL of mine came the same way. Pop the cover off and service it with grease and oil. It will make a difference.