How can I fix my Peugeot 206 Air Conditioning?

I just got a 206 (2006) - base model 1.4l The AC is making, what I can best describe as a buzzing noise but only while moving (I can distinctly hear the compressor motor). I took my car to the dealer who drove in the car with me and found the noise to be out of place. They have ordered another compressor however the 206 that I got on loan does the exact same thing. I'm concerned that his might be a common fault or worse, just the way that the AC is. Is anyone else experiencing this problem and is this normal? (I hope not as it is quite loud and rather annoying).