Bosch dishwasher not cleaning properly?

My Bosch is 10 years old. Mugs and cups still stained after wash. Have cleaned arms but no improvement. Upper tray worse than bottom. Cups in the corners worse than those near the middle. Still some smears of grease on pots at times. Tablets not dissolving occasionally. Have put tablets in with the cutlery - they did not dissolve. Have chopped up the tablet and put it in 10 mins into the cycle. The water seems to be hot but am wondering if its up to full temp. Any thoughts please ?