Hi I have a Blanco

Question

Hi I have a Blanco dishwasher BFDw8 which is having poor wash results in the top tray I have tried all the trouble shooting things in manual. Investigated further by opening door during wash cycle several times and discovered the top arm is not moving although water is still coming out of the arms. I did get a split pea particle out of the arm approx 2mm and have since had a mildly better wash and have used superior wash powder and rinse aid to try and help. Also have put a cleaner through dishwasher still have grainy finish on top shelf items. Arm is free to move.Can you helpMerrilyn