maverick et 732 issues

Well guys this is my second time using my maverick and im having some issues with it this time. Ive got around a 35 degree temp difference between the mav and my dial thermometer. Dial was reading 300 and the 732 was reading around 338 over shot my target temp of 275 so I brought the temp back down to 275 according to the dial gauge. The maverick slowly came down to 275 and kept dropping to 230 while the dial was still at 275. I checked my dial thermometer in boiling and ice water and its within 2 degrees just for the heck of it I tried another dial thermometer I have and it read the same as the other. Both probes are 1 inch below the grate and within a inch of each other. Anyone ealse had these issue? Is there a way to calibrate the 732? Im ready to toss it in the trash and stick to the old school way.

Yea only using the pit probe and its in the correct socket. I will do the boiling water test with the maverick just wasn't gonna unload the smoker to get to it tonite