Hygrometer help please!!

[mad4maduro]

Here's the deal -- I got my humidor about 2 years ago and calibrated my analog hygrometer (using salt method) at that time and popped her in the box....haven't touched it since. This summer I have been experiencing some pretty serious fluctuations in RH as I wrestled to get the humidor stabilized -- over the past few months I have noticed signs of high humidity (swollen or cracked foot here and there...some even split down the center -- not many signs like this -- but any at all is too many) -- I finally get the reading back to 70% (mind you...I had found some of those high RH signs at 70% prior to the fluctuations) -- By mistake I dripped some PG/distilled water solution on the hygrometer, right on the needle coil(open face style) and needless to say, the needle maxed out. SOooooo, I go to my tobacconist, was going to buy a digital hyg/therm and be done with it, but my guy said that the hygrometer should be fine -- just re-calibrate it. So I put some salt in a cap, dampened it, and left it in a ziploc for 8 hours. NOW it is my understanding that in that environment -- after that amount of time (at least 6 hrs) the RH should be exactly 75%, correct? So, I look at mine and it reads 90% after 8 hrs! Is that TOO much of a deviation OR Is it safe to assume that the reading should be 75% and back it off to reflect that reading OR should I just trash the thing and get a new one? I guess I was thinking that maybe it got out of wack..not having ever been re-calibrated since the first time 2 years ago -- but is 15% off possible? I was experiencing high RH type probs when I had a 70%reading so it makes sense that my reading was low. I did back it off to read 75% and put it in my humi and this morning, it read about 65% --- PLEASE--- I need INPUT!! Thanks!