Our ELECTRA AUTOWASHER AWM 1150A ECO washing machine appears cycle correctly except for when it goes on to SPIN. The motor speed inscreases to full speed but then slows down again and then increases up to full speed again an repeats that 3 or 4 times. It does not maintain a constant high speed spin. I have checked the Carbon Brushes. Plenty of carbon sticks left. Cleaned dust off armature and replaced. Any answers? Thanks, Lui Esposito