Recently received DSO2250-USB shows AC compensation loss due to GUI
screen position. The same effect of screen position occurs for
calibrated waveforms in both AC and DC coupled modes.

The two screenshots show the effect of shifting an AC calibration
waveform from the lower to the upper part of the GUI display.(CH2)

No other changes, but the loss of compensation is demonstrated.

Note that the internal PPKvolts measurement feature shows the reverse
effect. An increase in measured ppk is indicated for the waveform with
no overshoot/severe undershoot.

The compensation loss results in `7LSB distortion in the display, and
a 50mV difference in a 2vppk measurement.

Anyone know how this fault is achieved and how it might be corrected?

RL