After many users complained that the microphones on the iPhone 7 were malfunctioning, Apple issued an internal document to service providers about how to fix the issue.

Customers Speaking Out

Apple released the iPhone 7 in 2016. When it first came out, the iPhone 7 offered iOS 10 as an operating system. Users can now upgrade to iOS 11, which was released in 2017.

Since the iPhone 7 was first released, users were complaining about numerous malfunctions with the device. One complaint was about a hissing sound that the processor made at certain times.

In 2018, users complained about microphone problems with the iPhone 7.

"Ever since I updated to iOS 11.3 (the day it came out), my mic stopped working. I can no longer use Siri (like I ever used it anyways), no voice memos (can't even play old ones), can make calls but both parties hear nothing, video recording record without the sound," one user wrote on Reddit in April.

Other users are reporting similar or different issues such as FaceTime malfunctioning.

Apple has not publicly addressed the concerns.

Apple's Document

On May 4, MacRumors obtained an internal document that was originally sent to Apple Authorized Service Providers about the microphone issue. The document marked the first time Apple acknowledged the issue with the device.

In the document, Apple wrote that some users might not be heard during a phone call or a FaceTime session. It also wrote that users might see a "grayed-out speaker button during phone calls."

Apple did not disclose the cause of the microphone malfunction, but one rumor is that the recent software update is causing a hardware defect.

It's an "extremely rare problem, with a need for repair being rarer still," a source told Apple Insider.

Getting The Phone Repaired

The company hopes that service providers will use the document as a guide to provide repairs to users. To ensure that other devices are not causing the problem on the iPhone 7, service providers are instructed to ask users to disconnect external devices, such as Bluetooth headsets.

The grayed-out speaker issue can be diagnosed by running audio diagnostics on the device. A service provider can repair the device if it shows a "device could not detect dock" or "accessory not supported" message on it.

If the phone is under warranty, a user can receive a free repair. Even if it is not under warranty, Apple wrote in the document that service providers can repair it. However, the document does not indicate if there will be a cost for the repair.