I had this mishap with the Sidewinder X2, not sure what caused it exactly. The insulation cover came off at some point the filament just started melting around the block. How does the stock hot end handle PETG? I thought it would be ok, but maybe that’s the problem?
Hopefully the replacement hot end will be an improvement assuming it hasn’t wrecked the whole print head.
Before this I was printing PLA with no major issues.