The first person to point out the defect was Stephen Hackett, of the blog 512 Pixels. He first noticed the defect while restoring his phone from iCloud. Hackett eventually realized that the noise wasn’t coming from the speaker, but rather from the logic board itself. You can hear what it sounds like in the video below.
“This event was off the charts”
Gary Vaynerchuk was so impressed with TNW Conference 2016 he paused mid-talk to applaud us.
— Darrell Etherington (@etherington) September 17, 2016
At the moment, it’s unclear whether “noisegate” is endemic to all iPhone 7 Plus devices, or just a handful of defective models. Apple isn’t taking any chances though. Upon reporting the issue, a customer service representative told Stephen Hackett to return his phone to the Apple Store for a replacement.
This has lead many to suspect that processor is somehow to blame. Author and iOS developer Marco Arment described it as being “the phone equivalent of hearing the fans spin up loudly whenever your Mac’s CPU gets used to its actual potential”. Apple blog 9to5mac suggested that it could be some kind of cooling system, while others suspect the defect is due to “coil whine”.
Whatever it is, nothing has been confirmed yet. We’ve reached out to Apple for clarification. If we hear back, we’ll update this post.