K2 Plus CFS Filament Feed / Retract Issue

[Puzzler]

I’ve been having an issue with numerous feed and retraction errors on my 5 month old K2 Plus Combo. This initially seemed to be an issue with the Extruder but after fitting the newer extruder assembly, new nozzle, replaced all PTFE tubes with the spares that came with the printer, replaced cutter and run a full calibration, I get a problem where the filament doesn’t reach the extruder (see video) or sometimes reaches the extruder filament sensor but the CFS still tries to push filament through (this only happened once).

After looking online, I tried the spring modification (cut one loop off) and this seemed to work for a few prints but then the issue re-emerged. I have seen that some people recommend doing a 1.5mm washer / spacer to the CFS spring but not tried this yet.

I am able to print using the spool holder so know the extruder is fine so after any advice on what to try. I have a second CFS arriving tomorrow as wanted a second anyway so hoping this will at least get me multi-colour printing again.

any advice is welcomed.

[ChaosTheory]

Not an solution but ive been dealing with the same issiue for around 1 week

If i dissconect the CFS hub and pull out all the filament, reconnect the hub and push in the only filament i need it will restart again.

My K2 Plus CFS shows Error code FR2836. I have manualy gone over all the parts, tried cutting the spring, I can find no physical defaults.
My conclution is that it is ether a sensor or software related? Wasnt there an uppdate recently?

[ChaosTheory]

Heya i have been in contact with Creality, they told me to check the buffer if the filament reached it and if the light turned blue, have you done that?