I've noticed the same sounds from my 13 Pro:
- a constant, soft static sound when the camera is on
- a harsher, fast-switching electronic buzz when the processor is working hard
The latter sound is almost certainly
coil whine, which is a frustrating reality for a lot of electronics, but this is the first time I've heard it from a smart phone. A lot of higher-powered PC graphics cards make these sounds, and you can tell it's not the fans because it switches instantly as a result of how much an application is asking of the GPU.
The static I'm not as sure about. There are a lot of bits of hardware that only start running when you open the camera app. There are the cameras with whatever features like sensor shift, and the LiDAR along with other separate sensors. I don't know enough about the electronics in the camera package to point at any one in particular, but it's important to remember that it could all just be coil whine as a result of the very different power consumption profile the phone has when you're using the camera. The only sound I'm certain is
not coil whine is that faint clicking from the camera as tries in vain to focus on my ear from 5mm away.
Both sounds are extremely quiet. I have only noticed them when my fridge is off and the phone is face-up on a hard, shiny surface like the kitchen table or counter, or when I hold the back of the phone to my ear. That said, I'm a bit surprised that this is the
only thread I've seen on the subject. I wonder if all 13 Pros make these noises, but unfortunately you need very quiet conditions to test this.
