The first time I used mine I had the same problem. I had checked it a few times in the garage & again once before I ran it. then after the first pass I checked it again & it had lost about .5 Lbs. I set it back to the setpoint & its been there pretty much ever since. maybe .1 or .2 Lb variation, but not more than that. I ran it this weekend after >1 month down time & right back to where it should be.