The manual says that the yield monitor must be recalibrated when you change elevator speeds. You will need to weigh some loads and calibrate with new cal loads. There isn't any setting to change in the monitor.
Just started harvest in the Thumb of Michigan. Same thing 30-40%. Lots of volume. 200 per acre volume, but 48 test weight. After we ran it through our dryer it was back to about 53. My 1688 could use some more power at these moistures, especially dumping on the go, however we can only dry about 30 acres of corn a day.
Corn gets dried to 15.5%. Low BW is because of early frost and the kernals were not totally mature. Last year we had a great finish and bushel weights were high, 58 lbs. and more. harvesting 13% corn is just a dream here. Why do you let it get that dry, aren't you loosing weight?