Honda 2005 CRV noise

My honda mades a noise like a slide whisle, I think it is a belt slipping but can’t find anything in the owners manual about belts. Has anyone else had this problem?

Any More Clues ?

Under what conditions is the sound heard ? Does it do at all speeds / engine speeds ?
Are you most likely to hear it at about 1800 RPM and also at about 3600 RPM ?
Does it do this almost all the time ? Cold engine ? Warm engine ?
What do you have to do to get it to make the sound ?

CSA