While, sure, you calibrate on 10X, it sure looks like the device is showing a waveform that's not true.
I don't have a 1052, but I do have an 1102 (before the 100MHz hack was widespread knowledge) and it's happening pretty strongly with mine, Firmware 2.02.SP2
Here's something odd, too, if I push STOP and use the vertical adjustment, the waveform moves as expected, but as soon as I hit RUN, the falling edge continues to go below the screen while the next pulse's rising edge seems to have gone up according to the offset / 3 (see the attached params, shifted up 200mV on the display but the params show position at 600mV). Waveform looks and behaves fine at 500mV/div