Help Please: Can a Breville Barista Express (BES870XL) grind amount be recalibrated?

[kolding]

I have circa 2014 Barista Express (BES870XL), and over time, the grind amount knob seems to have slipped. I currently have the grind amount knob turned all the way down, and it's overflowing the basket. This seems to have gotten worse over time. Is there any way to recalibrate the amount of coffee it grinds, so that this is actually adjustable, or do I really heading to the range of having to manually control the dose every time? I've reached out to Breville support, but it seems to have fallen on deaf ears there.

Thanks...

Eric