Engadget Guide: Steps to Improve Poor iPhone Call Quality

Several of the fixes can be applied while a call is in progress. The report advises checking the volume and speaker output first, since the level may simply be turned down or speaker mode may not have been switched on, and then looking at the signal bars; if they are low, moving toward a window or a more open space can help.

iPhone users can also change the microphone mode mid-call. Voice Isolation is available on the iPhone XR, XS and newer models running iOS 16.4 or later, and uses machine learning to block environmental noise so the user's voice is more audible to the person on the other end. To turn it on, swipe down from the top-right of the screen to open Control Center, tap the small Phone Controls banner at the top, and under Audio & Video choose Voice Isolation in the Mic Mode section. Automatic is the alternative, leaving the phone to adjust for what is best.

Because these options affect the outgoing voice, the benefit belongs to the listener. Engadget notes that a user struggling to hear the other party should ask that person to try the same setting, along with the other steps, if their calls always sound poor.

If a call drops or the audio is bad, Engadget suggests ending it and forcing the device to reconnect to the cellular network: open Control Center, switch Airplane Mode on, wait 10 seconds and turn it off again. That pushes the phone off a congested or weak tower connection in the hope of a stronger signal.

Wi-Fi Calling, which routes calls over a Wi-Fi connection instead of a potentially weak cellular network, is offered as a good option where reception inside a home is poor. It is switched on under Settings > Apps > Phone > Wi-Fi Calling, then Wi-Fi Calling on This iPhone. Engadget cautions that the handoff back to cellular when a user leaves Wi-Fi range mid-call is not perfect and can cause drops.

Software can also matter. Apple regularly patches issues that may affect call quality, so the report recommends checking Settings > General > Software Update for the current iOS version and Settings > General > About for carrier settings updates, where a prompt should appear within 15 seconds if one is available.

Among the remaining steps, a restart is described as the oldest trick that still fixes many problems. On iPhones that use a SIM card, the tray can be removed with a paper clip while the phone is off to check for dust or a loose fit.

Hardware can be tested directly. Recording a voice memo and playing it back tells a user whether the microphone is working, and the speaker grill and earpiece can be cleaned with a soft brush. Thick or metal cases can interfere with antenna performance, so a call without a case, or on speakerphone, is worth trying.

Bluetooth headphones, AirPods included, share the 2.4GHz band with mice, keyboards, microwaves and baby monitors, and that congestion can degrade call audio. Making a call without headphones, or with them if they have never been used, shows whether the audio is any clearer.

Engadget also points to known hardware issues. Some iPhone 12 and 12 Pro models had high earpiece failure rates, which Apple addressed in a service program that has since closed, and older iPhones with Intel modems, namely the XR, XS and 11, may have weaker signal strength. Users who suspect a hardware fault can contact Apple, though the report says this will likely mean a paid in-store session.