Ugh, I totally forgot a few other suggestions for you, one of which is one of my own personal bugaboos about 3D printing.
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Others have suggested that the thermister (temp sensor) in the 3D print head is loose and may not be measuring consistently, which could result in your filament heating being equally inconsistent. The suggestion is to pull it out, and then re-seat it with a little thermal goop in there (like the thermal pastes you use for CPU cooling mounts in a computer).
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If the filament spool is providing too much resistance to the extruder gear, your filament itself can be slipping. Even if you’ve not calibrated your extrusion this would also potentially starve the nozzle sometimes. There are several suggestions here for improving how the spool rolls - especially thru the grommet in the enclosure which also adds friction, these may help. I added one here: Question regarding the filament holder
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Lastly you might have a bit of debris in the nozzle, or a partial clog. Make sure if you just park it up above the print bed, heat it up, and keep hitting the ‘load’ button on the touch screen it continues to flow evenly and doesn’t sputter or act a bit inconsistent. #5 about consistent heating can influence this too.