There is a hidden setting on the iPhone that greatly improves your voice during calls, it's called Voice Isolation, and as the name suggests, it isolates your voice while blocking ambient sounds during calls so that they sound crystal clear. It's a great feature if the people you're talking to have a hard time hearing you. This feature works on voice and video calls.
Note first:
◉ You must have an iPhone running iOS 15 or later, which means you need an iPhone XS or later.
◉ You can only turn on the sound isolation mode when you have already started the call.
◉ This feature needs to be manually turned on each time.
◉Not all apps support the sound isolation feature, including the regular iPhone app. For audio calls, we recommend FaceTime Audio. That is, the feature will not work when you call your friends in the traditional way through your local phone network, but it does work in FaceTime calls.
How to turn on sound isolation on your iPhone
◉ Open the FaceTime app and start a video or audio only call.
◉ During a call, open Control Center.
◉ Tap on microphone mode.
◉ Select sound insulation.
◉ When the call ends, the microphone mode settings will return to normal and you will have to repeat this process every time you have an audio only or video call to restart the sound isolation.
You can also benefit from sound isolation if you have an iPad with iPadOS 15 or later as well as a Mac with macOS Monterey or later. To access Control Center on your Mac during a FaceTime call.
Does sound insulation work with other applications?
The sound-isolating technology works with third-party apps, so it's not exclusive to FaceTime. Just the app developer needs to enable it.
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