iPhone 12 Pro iPhone 12 Pro "Hissing" When Charging

[jayvn7]

(I've also posted this in the troubleshoot forum but seeing as there's a wider audience here I thought it was also apt)

To preface I'm not sure 'hissing' is the correct word, but it's hard to describe. The closest thing I could compare it to would be the sound of a processor or fan "skipping", "whirring" or processing.

For context this is the phone's 3rd charge cycle, and it happened at about 92%. It was being charged from a USB-C charging unit, the same that charges my Macbook Pro. Once I (hastily) took it off charge, the noise stopped, so it's definitely related to the charging sequence.

Whether it makes a difference or not I don't know but I do believe the phone to have been "under load" when it started making the noise. When I did some general checks on the phone the iCloud backup screen showed that on the day before, it had backed up at around the same time the noise started this morning - about a minute's difference, so there's a chance it may have been related to that.

Obviously what I'm looking for is anyone who may have experienced this or something similar or who has any idea what it could be? My plan is to monitor it when I put it back on charge and see if the same thing happens, and in that event contact Apple.

 

[mikehoiu]

I had the same issue when I was using wireless charging over the weekend. I had to adjust the position on the mat but it went away after that.

 

[jayvn7]

I had the same issue when I was using wireless charging over the weekend. I had to adjust the position on the mat but it went away after that.

Ok that makes me feel slightly better that it's not just me! However this wasn't being wirelessly charged.. Could it be something to do with the angle/surface/position of charging?!

 

[ryry919]

Happened to me this morning around 5am. I thought one of my kids water bottles were under pressure from no water and making a hissing noise out of the valve so I checked them all and when returning to bed I still heard it and realized it was coming from my iPhone 12. It was plugged into the corded charger and my last iCloud backup was yesterday at 2:30pm so it’s not connected to that for me. As soon as I unplugged it the sound went away. I also restarted it and have been on my phone since (can’t fall back asleep now) with no hissing sound. Gonna charge it again and see if it returns.

 

[bluemarmot]

Same thing happening here. You've described the noise well. As soon as I unplug, the noise stops. I've tried multiple chargers (each with different wattages), and the same thing happens with the one phone. We've also plugged multiple iPhone 12s into the same chargers, and only the one phone makes the noise. Any luck resolving or any word from Support?

 

[kiralygabor]

I have / had the same issue.
I returned the phone 1 day later... they took it back and i received my replacement yesterday. SAME ISSUE again.
Doesn't matter if plugged into the wall or my mac, tried it with 5W / 10W / 12W / 18W/ 20W and 30W.
5 different cable, same issue.
Apple is gonna replace the phone once again.. Let's hope that number 3 is my lucky number..
Always 256GB and Pacific Blue.