"Speedster" Motor Speed Controller Fluctuating (bad resistor?)

recently bought a speedster at my semi-local hydro shop (40$)

http://www.greners.com/meters-timers/controllers/fan/duct-fan-speed-adjuster.html

many hours of driving later, we test it on out on our fan. our fan is a 340 CFM inline.

http://www.greners.com/fans-ventilation-filters/products/inline-fans-blowers/6-inch-fans/ecoplus-classic-inline-fan-6-340-cfm.html

upon plugging it in, the fan speed starts fluctuating on its own! without turning the dial, the fan was changing speeds from very slow to very fast. Scared for the well being of our fan we quickly unplugged it and took it inside for further testing.
we hooked it up to a desk lamp with an Incandescent light (CFL's explode if dimmed)
and the light started pulsing and changing intensities without anyone turning the dial.

my best guess is that the one we bought has a bad Resistor that fluctuates?
anyone else use the "Speedster" ?

currently going to return this one and see if another one works. (my semi-local hydro shop is an easy 200k of driving )
any input is greatly appreciated

ClamDigger

i hate to bump my own thread.....
bump!

no one uses a speedster?

I just got one on a return he said it wouldnt adjust his speed it just gets really hot. Id like to know what caused your problem too. It would either be the capacitor failing or a resistor.

I've got one running the exhaust on my drying box, can't say I notice any variation but I don't pay much attention to that.

I would call the shop and go ahead and exchange the item
best to do it right away rather than wait for the problem to get worse