they must of fill them when they were hot which means when the tire cools off the preasure is lower.

 

My fit is about 2 months old and i had the same prob. My tire pressure meter told me 32,31,32,28. I filled up the one that was 28 and after a few miles of driving it turned off. This happened about three weeks ago and it hasn't come back on for me. I even drove it about 1200 miles in the three weeks too. The TPMS may have come loose or it was just a fluke like mine.