Issue: Teflon tube of the bowden extruder is slightly rotating around its axes in its connector to the extruder, just for a tiny angle with HotEnd moving back and forth.
Solution: add a holder and strain reliever. Simple, ~35 min print, but effective. Hope it would prolong live of the teflon tube.
Use 2 x M5x10 bolts and M5 T-nuts to mount to frame. May require a fine touch slightly enlarging the diameter of the tube holder; by a file or a drill... Still keep it tight, should work like a lock for the tube.
Print flat as shown on the picture...
25% Gyroid or quarter qubic