This is funny. I just kegged my first brew and I have noticed the same thing. It has gone down like 3psi in just a few hours after being stable for a day.
I was thinking that maybe it was the keg and the beer cooling that had an effect on the psi.
It has gone up and down probably 3-4 times??
Must be somewhat normal if we are both experiencing it.
Next Brew: Cascades Orange Pale Ale
Primary: Indus IPA
Secondary: Belhaven 80 Shilling
Carbing Up: Simply Hefe
On Tap: Fat Tire, Watneys Cream Stout, Bombshell Blonde