Hi … yes, resolved it by making sure that the device screwed attached in the rear of the case where the filament pushes through is clean, well greased, the spring inside isnt stuck and the slider inside being pushed by the spring is freeling moving. Its what loads the filament giving the filament an extra push when it reaches the extruder. If the spring is stuck or slider isnt freely moving, seems Bamboo didnt put much grease there, it doesnt push the filament enought to load it in the extruder thus, the filament reurns a little after it reaches the extruder.
Best approach is to unscrew that plastic box, careful not to have everything fall apart on you, clean it, grease it and move the slider and spring a bit to make sure its fully seated, sliding and functional before putting it back on again.
Hope this helps and fixes your issue like it did mine.
Thank you