Deafening screech / squeal iPhone 6

[W1ES]

After over a year of having this happen, I've had my phone just start to screech/squeal a high-pitched noise whilst talking.  The person on the other end doesn't hear anything amiss.  It's loud enough to physically hurt my ear.

iPhone 6s+, using wifi and VZW Wifi, iOS 11.4.  Since this latest software update, I now also randomly get "No Service" in the upper left that will magically re-appear after a bit.  I have not had the screeching when off wifi.

Wifi consists of Google wifi mesh system with 2 nodes.

I saw one person solved their problem 3 years ago with iOS 9 but the menu tree has changed since then so that I can't find my way in to turn "advanced voice" off (perhaps this option is no longer available).

I'm about to get rid of this phone unless the issue can be resolved.

[vzw_customer_support]

W1ES,

Updating software on the phone should be an easy task with enhancements that will help improve the experience with your device. I am concerned to hear that was not the case with your phone but we will work to get this resolved for you. Are you noticing the same issues happening when on speakerphone, Bluetooth or via the headphone jack? How often do you notice this happening? Is there a pattern that you can see when you begin to hear the noise on your end?

Candice_VZW
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