Are you printing with PLA? if your hotend fan is not cooling the aluminum pinch wheel enough or you decide to reduce fan speed or even turn off fans when printing, this is what you get. I did that before. make sure your fans are powerful enough and cooling the aluminum pinch wheel enough. Also make sure the air circulation is good. no heat accumulate around the hotend
(Da Vinci 1.0, Jr. 1.0 RAMPS, miniMaker) X4, (Creality CR-10S, CR-10 mini, Ender-3) X4, Anycubic MEGA X4, Anycubic Chrion X1, ADMILAB Gantry X2 (MonoPrice Maker Select V2, Plus, Ultimate)X4--Select mini X1, Anycubic photon X4, Wanhao duplicate D7 X1.
iNSTONE Inventor Pro X2, CTC Dual X2, ANET-A8, Hictop 3DP-11, Solidoodle Press, FLSUN I3 2017X1