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Just writing a note following a meeting with my dealer on Monday 5th July:
My car has a noise that is sometimes worse than at other times;

On Monday it was not loud but I think still present;
I don’t think it is a normal noise;
It is most commonly heard when the transmission is changing down and revs increase;
Some would say it is a noisy noise. Some kind of whirring or vibration that stops when you turn off the A/C system;
I have tried everything to reproduce the noise without success;
It is still there today;
I suspect it might be much more pronounced on hot days when more cooling is needed;
That might be why it is not loud this week (Cold in Australia);
It still causes me major grief when other people complain about it and particularly my wife;

Can anybody identify a similar problem?
Do you have a noisy R350? I hope not.
I look forward to hearing from you.

Thank and regards, Skerg