Recently I got a jammed extruder very often. It is not the nozzle which is jammed but more upwards. When I remove the filament and put it back in again it works, but later at some random moment it gets jammed again. I have been using PETG lately which need a high printing temperature of around 270 degrees. What could be the cause of these jams? Can the PTFE detoriate because i use these high temperatures? I am reading up on this and at several fora I found max temperatures for the ptfe which were below the quoted max temperature of the Creatr HS, like 240 and 260. Is anybody aware of some full metal replacements which fit the Creatr HS? Because I am getting really fed up with all these jams.