My dishwasher has been not cleaning properly lately and doesn't dissolve the wash packet out of the soap dish. I cleaned out the filter a couple of weeks ago and it seemed to get better but now it's doing it again. I tried it once on heavy wash and it seemed to clean/dissolve but that seems like a poor long term solution. When it's on normal wash it doesn't sound like it is running properly, like that is a dull hum, rather than the kind of motor noise that it normally has after it first fills with water. (it still DOES have that sound on heavy wash) I just looked up the date of this appliance and it is from march 2000. (it was with the house when I bought it) Is it time to buy a new one, or can I repair it?