I just picked up a 2008 XC V8 and all is well. At idle I can hear a very faint whistle noise coming from the engine bay. Once under way it cannot be heard until idling again. The noise is consistent with volume and always at idle. I had a Volvo mechanic listen to it yesterday and he said all is normal and there is nothing to worry about. I have searched around online and cannot find another entry for this condition so I am thinking maybe the mechanic is correct. Just looking to see if anybody has had a similar noise from their XC.