I own a HealthRider H90e. It has a resistance control problem; the resistance will increase, but then not return to a lower resisitance, even though the display shows the requested lower level. I purchased a replacement motor from you, Healthrider H90E Elliptical Resistance Motor Model Number HREL598080 Part Number 241949. When I plugged the new motor in, I observed that the new motor responded to requests to increase the resistance, but would not respond to a request for a lower resistance. Is this likely to be a motor control board issue and if so, is there a replacement board available?