Apple on Tuesday released a minor iOS 11.0.2 software update for iPhone, iPad and iPod touch following the bug-fix iOS 11.0.1 update which dropped a week ago.
iOS 11.0.2 resolves an issue with a crackling or static sound that some iPhone 8 and iPhone 8 Plus owners reported hearing through the earpiece during cellular and FaceTime calls.
Apple’s latest software update is available over-the-air in Setting → General → Software Update and carries a build number of 15A421.
Apple’s official release notes state that iOS 11.0.2 includes bug fixes and improvements for your iPhone or iPad, including:
  • Fixes an issue where crackling sounds may occur during calls for a small number of iPhone 8 and 8 Plus devices
  • Addresses an issue that could cause some photos to become hidden
  • Fixes an issue where attachments in S/MIME encrypted emails would not open
For information on the security content of iOS 11.0.2, consult Apple’s security document.