I just felt this the other day for the first time at about 1300 miles. It was just after starting the engine from cold (well, it's SoCal, so not cold. But, cold engine, about 60º ambient). It felt like a friction halfway through the pedal travel, as if the cable was rubbing against something. After a couple of minutes it went away. I wasn't planning on taking it in unless the problem persisted. But, if you're taking yours in, I'd be very interested to hear what they say.