Yup. The H/K's fan comes on early (after about 30 minutes of being on) and often (every 10-15 minutes or so). And it is indeed quite loud.
I'm not exactly sure what goes the deal is with the H/K's. Some people have them and report that their fan never comes on. My fan will come on consistently even if I turn it on and immediately put it on "mute".

Perhaps it's a thermostat tolerance issue or something, and my unit's thermostat is calibrated on the "touchy" side of the spectrum.
The vent hood works, though. Messed around with Avia for about an hour, then watched 3 30-minute TV episodes. The H/K's fan stayed silent the whole time. Woohoo!