Hi all, Just wondering of others here have found this problem with the Regency I2400. When the damper is set to half or less, and the blower fan is off, the unit produces a whine, or hum. It's a high-pitched noise that is really annoying, sounds likes like its caused by a very rapid and slight metal vibration from air movement. I've heard from my installer that there have been a few complaints of this. Anyone here have a similar experience? Anyone know what to do about it? Or if Regency has addressed this? All advice is welcome, the retailer so far has denied hearing of any problems of this nature with this unit.