On service after 15000km they compensated 30 "lost" grams of freon, and after that, my A/C is not leaking any more, but now it is howling, the warmer weather, howling is louder. When it is turned on and outer temperature is greater than 30 Celsius, it is wery annoying, and A/C is turning on and off (compressor only) rapidly (2-3 sec. on, 2-3 sec. off). Inner temperature is OK. Think that I have pressure problem. I went to service on 30000km., told them about it, but nothing is done, everything is OK according to them.