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
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