Hi, I am desparate and willing to pay anyone that can help solve my printer problem for me.

S3D support and Craftunique are unable to isolate despite much problem solving.

PROBLEM:
Random and slightly diagonal lines/streaks across my PLA prints.
1.5yr old Craftbot3 (CoreXY design) with moderate usage.
Problem only started recently.
Started on head1 then eventually started on head2.
Layers are about 1-2seconds long

SOLUTIONS TRIED:...