Same here, i manged to reduce the problem using a low viscosity grease or oil, but is temporary.
I thinkig in trying some this solutions that i saw surfing in the internet
- an aftermarket upgrade for the lineal bearing (self lubricated) in the extruder head
- an aftermarket upgrade to a linear X rail instead of the ciurcualr one.
- Change de belt to a 8mm instead of the 6mm.
This problem is driving me crazy.