Livio, squeeling is usually, on a hard compound, caused by the pad vibrating, but since your pad isnt that hard i would look at means to solving it or reducing it.
Rd pads squeel when not aligned properly and vibrates, and this typically means the front of the pad is touching before the rear. Try this first though.
A series of stop from 60-80mpg to 5mph, at no point must you stop of pad material can be deposited on the disc and cause vibrations (this is also ALWAYS the cause of a vibrating pedal and mistaken for as a warped disc, if you actually know how hard it is to warp a disc youl understand, unless there is disc runout and thats usually dirt between the disc and hub).
Anyway, from 80 or so start with light braking force till you reach about 5 mph, then turn around and do the same but get progressively harder on the pedal. Do this over 7-10 runs till you are finally stomping on the brakes. But leave a little cooldown period between each run, typically the turnaround and speedup time is sufficient. This will bed the pad properly and is the correct way you should do it from new, the 200 mile method is time consuming and doesnt really burn the resins off as your meant to.
If this only works a little take your pad carrier off, chamfer the leading edge of the pad and apply copper grease to the back, or an anti squeel backing pad. Check the caliper slides aswell, the carrier should slide effortlessly along the slides, but corrosion means the front slide somtimes becomes sticky.