It’s not the QC or the calibration. It is the Boss pedal. I have 2 Boss FV-500Ls that do nothing for the first 20% of travel, and an EV30 that does nothing for the first 30%. It is simply the poor way in which the pedals are engineered, such that the pot control simply does not move before that point in the pedal travel. Others have reported the same problem. You would expect better from Boss, but it is what it is.
The QC can only calibrate a change in resistance. If the resistance does not change for the first 20-30% of travel because of the poor engineering of the pedal, there is nothing to calibrate. The only work around I have found is to physically put a block under the back of the treadle. It reduces the pedal travel but at least the travel that you do have actually does something.
I have now bought a couple of Fractal pedals - they work perfectly, and every mm of the pedal travel has an effect in the QC.
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