Hi, I also use XT and agree with the replies about speed.I've found the optimal settings for XT seem for me to be:
242-245oC nozzle temp
Bed temp of 78oC
layer size .2
All speeds constant - 20-30mm/sec
minimum of three shells (3x nozzle thickness)
The 10mm speed is too slow, XT clear and White seem to be most affected by this leaving brown or burnt marks embedded in the print. I spent quite a while trying to get my settings correct, everything I tried at 0.1mm left a lot of burn marks, if you really need to print at 0.1
try.....
237oC nozzle temp
bed temp of 78oC
Layer size 0.1
all speeds at 30mm/sec
it'll be slower but should help, also ensure you dont have any restrictions in your extruder path, I've also seen problems with too much tension on the spool causing an underextrusion and what look like burn makrs in the print until I changed to the iroberts V2 extruder - https://www.youmagine.com/designs/alternative-um2-feeder-version-two
hope this helps, XT can be quite picky to work with, have you considered NGen ?