This dishwasher is emitting a rattle or scraping type noise during operation that I believe is coming from the bottom wash arm. When I spin that arm manually it wobbles and makes a similar noise. I would say it seems like a bad bearing but I don"t know if there are actually bearings in the design.

In addition the wash arm under the upper rack might not always be spinning. I put it in a specific position, ran the dishwasher for a few minutes and then opened the door to find it in the same position. I see that wash arm is fed by a water line from the bottom arm so I'm guessing these two issues are related.

Suggestions?