I posted about this awhile back, but I have since made changes and it is still doing it. Basically I have a Flashforge Dreamer with a DuetWifi board and Titan extruder with E3D v6 hotend. It prints better than ever when it works, but part way through a print it will start grinding the filament and I have to pull the filament out and re-load it. I have tried reducing retraction down to 0.8 mm even. Any help would be appreciated as I'm kind of at a loss.