Second iOS 11 update eliminates the crackling noise during phone calls with the iPhone 8.
Apple has just unleashed their second minor iOS 11 update with build number 15A421. It’s available for iPhone, iPad and iPod devices, bringing a number of fixes and improvements, most notably of which is the fix for the crackling audio during phone calls with the new iPhone 8 and iPhone 8 Plus. We’ve reported last month that some iPhone 8 owners experienced strange noise coming from the earpiece during phone calls, and that Apple promised to fix this bug with an update.
iOS 11.0.2 also fixes the bug that causes some photos not to show up in the library, and an issue related to email attachments. Additionally, Apple mentions in the changelog that this release brings some general improvements for iPhone and iPad.
Apple officially rolled out the iOS 11 update on September 19. iOS 11.0.1 was released a week later to fix some bugs with the email accounts.
You can update your device by going to the Settings → General → Software Update. Make sure that you have at least 50% battery charge remaining.