I'm trying to figure out how you trigger auto flushing just by leaning over. Meanwhile, auto flush on most public toilets I've used has a 50-50 shot of just not working at all, so I have to find the manual button.
At least for me, I know that I have a small butt and don't sit all the way back against the seat (there's quite a lot of space), so often these sensors don't catch me in the first place. Do you lean so far you move away from the sensor or something?
Regardless, both of us have relatively unique problems, I think. These sensors have been tuned to the average ass.