See Rescheduled timer in the past
This is indeed an error caused by too high step rates.
Lets assume
- full_steps_per_rotation: 200
- microsteps: 64
- rotation_distance: 32
- velocity: 100
So, if I did not botch the math:
steps\_per\_mm = \frac{full\_steps\_per\_rotation * microsteps}{rotation\_distance} = \frac{200 * 64}{32}=400
and
steps\_per\_sec = steps\_per\_mm * velocity = 400 * 100 = 40000
with a 20 MHz AVR having a total step rate of 123000 steps with 3 steppers.
So with 40K steps per stepper (X, Y) you should have a bit of leeway. Note, however, that these are theoretical and synthetic maxima, which do not take into account the fact that your printer has a few more tasks than just feeding the steppers.
Also, I have no experience with these 8-bit boards under Klipper, so it is hard for me to say what a realistic expectation is.