Yeah, this can happen. It's either due to the silicone getting stuck under the plastic edge of the rotary or a faulty unit.
First try mashing on the rotary some. Try to work the edges of the silicone toward the center of the rotary. Often this fixes the issue.
If it doesn't fix the false triggering or it comes back later then I would say you should exchange it for a new board. Preferably through the vendor you purchased it from, but if you're outside of their exchange/return period then send us a support ticket here: http://www.keithmcmillen.com/support
and we'll get you taken care of.
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