Viking Dishwasher leaves a film on the dishes

Question

My wife tells me the dishwasher leaves a white residue on glasses and table ware. She has reduced the soap (cascade liquid) to one teaspoon per load and still the problem continues. She ends up hand washing everything after running a load. The file does come off when hand washed. I turned up the water temp but that did not help..Dishwasher has started leaving a fine grit on dishes