Ok so I was wondering if anyone has had this same issue with their Volvo I am having. I took video of the noise I am getting under the hood. I think it may be related to the AC but can't tell for sure. I will do some additional tests tonight as long as it doesn't rain! I took video of the sound with the hood open. I see the altenator but can't tell if there are additional pulleys down in that area. Please let me know if you recognize this issue or if you have any sugestions. I will update later tonight if I get a chance to run tests with an without the AC running.