I just set up a 6055 with a 7091 controller. It worked for about 10 minutes, only problem was a fairly loud click when the unit switched to on. 10 minutes later it wasn't working at all. When I plug in the power supply unit, the green light is on but flashes brighter every second or so. When I plug in the connector (1) into the pump (3) the light dims and alternates between off and on with the same periodicity. The green light on the 7091 also flashes with the same periodicity. I am plugged into a power strip with a built in GCFI. I don't know if any of this info is relevant. Also, the fit of the propeller housing is a little loose.