I'm having problems with:

DRIVETRAIN:
Shimano 105, 30-speed Shifters and Derailleurs
FSA Vero 3-Piece Aluminum Crankset with 50/39/30T CNC 7075/T6 Aluminum Chainrings

and am pretty much a noob at this. I'm sure the bike shop will fix it for me, but I'd really like to become more self-reliant.

The middle gear of the front gearset is losing the chain every rotation. The chain isn't hitting the derailer at all... it's just that every cycle of the gear the chain loses its seating and starts riding on top of the teeth rather than set down between them. This causes one of two things to happen... either the chain clicks back into place with a small jerk, or the petals simply spin under the chain causing a grinding sound and difficulty pedalling. It seems to be worse when the rear gear is set to the middle gears rather than the very large or very small.... pretty much right when you should be using that gear. The larger and smaller front gear are not having this problem.

Any hints before I take it to the shop?