Whirpool Quiet Parter only drains when press cancel?

On some cycles on my Whirlpool Quiet Partner II (DU1145XTPQ3) the water does not drain out. If we press the cancel button, it will drain. If we accidentaly hit another button, it will fill with more water and it will overflow. There have been a few times where we have not run the dishwasher and what seems to be waste water will accumulate in the dishwasher. This seems to happen when we run water in the sink, but not everytime, by any means. Canceling will remove the waste water.
Any advice on what to check on this problem that appears to be multi-faceted.
Thank you