It was running flawlessly until the dealership changed the rear pads + turned the rotors. A couple of weeks later I started hearing a growling noise when I drive in/out of parking spots with the brakes disengaged, the noise disappears as soon as I start driving but comes back right after I apply the brakes (never during). Returned to the dealership a few weeks later, the mechanic concurred and said he made some adjustments. A week after, it started to make the same noise and would progressively get worse but sometimes I don't hear it at all. Initially, the noise came from the rear pads, now it is coming from just the rear right wheel.
What could this be? Cheap pads? Bad rotor turning? Calipers?

 

Unfortunately you will need to take it back for them to rectify.

 

How many miles were on your car when you had the dealer do the brakes?

Why were the rotors turned?

 

35790 miles. (57000 km) The note on the work order: Found rear brake pads at 2-3 mm (0.12 inches). As for (why were the rotors turned?) I don't know.
After about a month of driving, the brake pads stopped dragging, assuming enough wore out to make room between the rotor and the pads!

 

I left a message for the service manager but got no reply. needless to say, that dealership will not be doing any service on my two Mazdas and i will be buying my next CX-5 somewhere else.