Make and receive high-definition voice calls (Clear conversations and reduced background noise)
INSTRUCTIONS & INFO
To turn AT&T HD Voice on or off, swipe down from the top of the screen, then tap the Settings icon. Note: To use AT&T HD Voice, both caller and receiver need an AT&T HD Voice-capable phone and must be located in an AT&T HD Voice coverage area.
Swipe to the Wireless & networks tab, then tap More.
Tap Cellular networks.
Tap Enhanced LTE Services, and tap the Enhanced LTE Services toggle to turn AT&T HD Voice on or off. Note: Turning off AT&T HD Voice will also disable AT&T Video Call. Learn more about AT&T HD Voice.