Same with me, it only squeak when slow speed and light brake e.g. driving in the parking lot. Porsche also says this is normal. Sometimes, I feel embarrassed when driving next to another in the parking. My car sound like an old school bus

 

The high pitch squealing on my 10' P4S is really tiresome, took it to dealership twice, said its normal for it to squeal. they said still have roughly 9-10months worth of pads still. But the damn thing high pitch squeal is unbearable and down right embarrassing for a porsche. freaking thing squeals like a big mac truck or school bus braking, even when I'm braking from 20 mph and slowly braking. Go firgure for a 100K Plus car, you shouldn't have this crap.

Thinking about changing pads and having the anti-squel slap on.