Does the humidity vary a lot between parts of a humidor?

[Paraphen]

I've got a desktop humidor with one tray and space below it, and I've been using a perforated plastic tube with Heartfelt beads, just setting it on the top shelf. The hygrometer has always stuck to around 65%, so I figured everything was fine.

But the cigars in the bottom seem a little dry. So as an experiment, I moved the beads to the bottom section, and now the hygrometer, which is sitting on the top shelf, only reads 58%. Could there really be this much variation between the two levels of the humidor? I mean, the tray is only a couple of inches above the bottom of the humidor.