The Dual Extrusion Module for Snapmaker 2.0 causes the same user reports of seemingly clogged nozzles. My theory is that it is not about heat creep/clogged nozzle, but either the retraction settings (the filament shavings observed here in this thread IMHO support this theory) and/or some feeder design problem (the feeder lock levers being to weak). I personally plan to change retraction settings and printed the lever blocks as Snapmaker suggested as in interims solution and will see how far I get (but as I am a low-frequency-printer - I’ll not have feedback very soon). More details here: Dual Extrusion Head: Heat creep? More likely: Bad feeder!