Hubby took apart dishwasher, cleaned out the debris inside and discovered that the chopper was broken. Probably had been for a while. Replaced chopper and now the dishwasher works as good as new! Probably took him about an hour total. He's a pretty handy guy, though, and had all the tools he needed on hand. He also replaced the tube running up the back of the dishwasher. Not sure this needed to be done, but the flappers seemed not to be going closed as they should.