Ive had my head under the bonnet today, and found a strange hiss coming from around the high and low pipes on the air con, it seems to be coming from where the two pipes go through the the engine compartment into what i would class as the top compartment of the engine bay where the round drum is (speedo) i think i could be totally wrong with that description. the pipes go through the panel and have a rubber sleeve round them its above the topup valves. only hear a hiss there, is this normal? i cant feel anything and the pipes defiantly get cold with condensation appearing on. the system was refilled and dye added also cant see any dye around that area.