I trust the Bovedas. If they're not drying out, your hygrometer may be off.
I used to worry about the numbers, but ever since I added Bovedas to my humidors, I just go by them. Got about a dozen or so in each humidor with about 4-500 cigars each. I also keep a pound of heartfelt beads in each. When I see a Boveda start to go down, I overcharge the beads and the Bovedas plump back up.
I dont have a wineador but I don't think the process is any different. I know some people add circulating fans.
Could be the low stock in there allowing for fluctuations. Throw some empty boxes in there if you can. Or fill it with cigars