2018 CX-5 Siren/Whoop noise

I just wanted to let everyone know this forum helped me with this issue. I took a video I saved of the siren sound and referenced this forum along with another that I found stating Mazda is aware of the issue and has a hotline established.
It is the expansion valve and Mazda ordered the larr for me to be replaced under warranty even though the tech did not hear the sound. Because it was so intermittent, I had a video, Mazda is aware of it, and my description correlated with previous repairs they had done. Sharing this in case it helps anyone else! It took me about a year because the dealership previously said they had found nothing wrong 😑
(The invoice screenshot is not mine it from another forum I soind
Same on my 2020. The dealer refuses to change the valve and Mazda Hotline is not approving the repair if they can't replicate it. I contacted Mazda and the same, and nothing will happen if they can't replicate it. I'm getting the sound more and more and I'm taking it again next week. This is very frustrating and I'm amazed and Mazda's lack of support. Even if I recorded video myself...

If anyone knows someone in Mazda that can help would be great. I'm a month away from the end of my guarantee.

Got a call from the dealer. That Mazda is aware of the issue but there's nothing they can do and that it's normal to make that sound sometimes... Still can't believe this.
That's BS. Someone is not telling the truth. It's not a normal sound. They are trying to get out of it, you have to be persistent. I'm the original poster of this link and I went through a lot to get them to fix it. They finally replaced mine and the noise quit. Now they have a hotline for it so they are completely aware of the problem. Ask them why other people called the hotline and got their Mazda fixed but you didn't. Maybe legal action?
The service tech pulled me aside and told me he knew exactly what was happening. It's a manufacturing defect of a piece in the expansion valve. Mazda Corp. kept fighting it. I told them I'd make a deal with them. If they replaced the expansion valve and the noise went away, it was on them. If not, I'd pay for it. I was so sure of it I knew I'd be right, and I was. I saw the same thing on other car forums I researched.
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I had the whooping sound and it self resolved when water poured out of the AC system, there was a small puddle of water under my car on a humid day. That was a while ago.