I have worked on Mitsubishi EDM's for 10 + years. Mainly SX models. My company just dropped a CX-20 on me and I have an issue. At random times the neopreane roller will turn backwards and roll the wire back through the head to the spool. Mostlw after a wire break. It pulls with so much force I cannot hold the wire if I grab it. I have had it running for 6 months and it started out fine but now its a problem. Anyone else have this issue? Overall its a great machine for the few bucks we got it for. Thanks?