Whirlpool drains during wash cycle

My Whirlpool dishwasher fills properly, I have checked water level after fill. The wash cycle begins, it sounds like a normal wash with plenty of water movement. After running about two minutes it pauses (may be normal), then runs about two more minutes (normal water sound) and pauses again. At this point the water pumps out of the washer (I watched hose under washer and you can hear it draining into the disposal), then the dishwasher begins washing again. There is no water in machine and it will continue the complete cycle making a humming noise from lack of water. I would appreciate any help at this point.