High pitched chirp when call connects

[helicopter96]

I'm running 9.0.1 on my iPhone 6s and when I take a call, as soon as it connects there's a high-pitched chirp that's very bothersome to hear with the phone up against your ear. Is anybody else experiencing this?

 

[jlaw]

https://forums.macrumors.com/threads/6s-chirp-before-connecting-a-call.1922687

https://forums.macrumors.com/threads/iphone-6s-chirp-when-dialing.1922736/