Please help!!!

I am somewhat new to cigars and very new to humidors. Recently i bought an acrylic jar humidor, a hydroset II hygrometer, a drymistat tube, and a xicar jar. I calibrated my hygrometer, and it read a perfect 75% with the salt test. When i put the hygrometer in the jar with the tube, as well as with the jar (but at separate times) I have found that the humidity skyrockets to around 80% when these products say they will keep a 70% humidity. Has anyone else has this problem? Or have any suggestions? Please help I have 12 Gurkha grand reserves that need some storage so your help would save them!