Gotta wait till the weekend so I can read all of the threads about how to use this new precision instrument properly! (It's absolutely necessary I convince my wife this new purchase was warranted with the best butts she's ever tasted! )
As an aside....I'm a little surprised that the water pan (sand for me) is so shallow................
the sand is a little different since it holds the temp longer, might want to just try closing down the vents a little earlier than you are used to with water.
I think you are right about the vents however I should have stated that sand with the combo of Basques hardwood lump (which runs hot) is not a good combo for me.