Problems with Western Caliber III Hygrometer?

[BlackDog]

I'm wondering if anyone has had problems with their Western Caliber III hygrometer? Mine doesn't seem to be holding at one point.

A little background:

I have 3 storage devices, all with Shilala HCM beads. All have the quantity of beads Scott recommends for the volume of the storage device. In my coolerdor I have an Acu-Rite Digital Hygrometer you can buy at Walmart for about $7 - $8. The coolerdor has 65% beads, and the hydro holds steady at 66%. No problem.

In my flip top mason jar that Shilala bombed me with, there are 67% beads, and a HygroSet Adjustable Digital Hygrometer that Scott calibrated and included with the bomb. It holds at 67% perfectly.

In my desk top, I've got 65% beads and a Western Caliber III hygrometer. When I calibrated the hygrometer doing the salt test, it came in at 62%, and I marked it with a "-3" so I would remember it was 3 percent low. Recently it had been reading 59%, and I assumed I needed to put some moisture back in the humi, so I put some distilled water in one of those black plastic dealies with the green foam inside, and put it in my humi. The hygrometer crept up to 60%, and then dropped back to 59%. Of course this made no sense as I put more moisture in the humi. So I took the HygroSet that I got from Shilala and put it in the humi. After a couple hours it was steady on 65%, just like it should have been since I have 65% beads in there.

So I can only assume that my Western Caliber III is no good since it 1) won't hold at it's normal deviation from the 75% salt test, and 2) dropped back to 59% even though I had added more moisture to the humi.

Do any of you have suggestions or thoughts? Is this Western Caliber III junk? Thanks for your help!