Alternator whine

cwhawk

Has anyone noticed a whine coming from the alternator? I am not talking about noise coming into the radio. When the alternator is not charging, and you are driving on a smooth road, you notice a whine between 2000 prm - 3000 rpm. The Nissan dealer changed the alternator at a cost of $800 to the extended warranty company, but the new alternator is just as noisy. They are checking with Nissan to ask if something else is causing the whine. As an old timer, I believe it is the alternator - new or not. When you reduce rpm, the whine decreases. If you have the AC off, and are sitting still, you can make the whine go up or down as the RPM changes. When the alternator is showing 14.4 (charging), the noise is not there.
If anyone has this problem or has had it corrected, please let me know.