Hi, after some advice, have had new MOT today, flew threw - happy days!!!
When it had cambelt Audi advised 'sqeaky' AC compressor, this was March 08.
Noise has not got any worse since, the mechanic had a good look at it for me today as I'm off to France in Sept and Oct, he says that the noise is probably coming from aux. belt tensioner.
Got home tonight and decided to have a look, checked the tensioner by releasing pressure of belt and seems fine - no play and nice and smooth.
Car was idling and I tried to pin point noise, couldn't and then remembered AC issue raised previously.
Switched climate on and set to 19, noise stopped.
Climate off, noise back and vice versa.
I'm leaning more towards the AC compressor being on its way out
Could it be the extra load of the compressor is taking up any play in the tensioner.
Car is A4 Avant 54 plate tdi 130 Sport.