Need Help, Name That Subie Brake Issue!

My wife's 2011 Subaru Outback has developed a brake issue. The symptoms are soft brake feel (brake pedal travels farther than usual until brakes actually kick in) and when I get in the car after it's been off for a while, the brake pedal is firm as if the car didn't have power brakes at all.

The problem is, we currently live in Central Florida, and the local Subaru dealer has been REALLY bad with this car, so it'd help to know what I may be looking at when I take it to get it fixed. They are just going to start replacing parts until the problem goes away. The extended warranty is coming in handy. It's actually paid for itself in tires alone, which the this warranty covers for some reason.