Have a Quadra-Fire Bodega Bay insert (wood burning). Blower is pumping out much less air than previously. You can now turn the fan speed control all the way up, where in the past it was too noisy and shaky at full speed - you'd have to back it down a bit. I jumped the fan control to see if that was the problem - no impact. Brought the fan into the dealer - they say it works fine and is up to spec. Any ideas? What would cause a fan to suddenly run slower at full voltage? You can't feel any air flow 2 feet in front of the insert. Thanks,

Steve