While we all love having our phones they are far from perfect. Sometimes strange things happen that almost have no answer. Like phones that consume mobile data without an explanation and increase the owner’s bill. Or spraying out information that anyone around you can pick up. Radio frequency interference or RFI is an interesting phenomenon. Now some are experiencing their iPhone leaks sound to their AM radio. That’s not how infotainment is supposed to work.

The sound leak happens if the radio is tuned to 950-970kHz

We’re talking unintended audio leaking from the iPhone and the AM radio picking it up. The phenomenon happens if the radio is tuned to 950-970kHz. Some phones are able to transmit audio from as far away as 20 feet. Basically, it’s your iPhone interfering with your radio. It sounds like those crackly police car communications from 1950s movies. But the sound coming from the iPhone can drown out whatever you’re listening to on the AM radio. 

This seems to be happening with iPhones 7 to 10 mostly. There are reports that it is also happening with Motorola Android phones. The amplifier circuit of the iPhone’s speaker is probably what transmits the audio, and the volume your phone is set to can make a difference. As a security risk, it is probably not bad. From a legal standpoint, the audio leakage falls within the FCC’s Part 15 allowances according to hackaday.

Should your iPhone be completely off if you’re around an AM radio?

Whether it is a matter of functionality we can’t say. Should your iPhone be completely off if you’re around an AM radio? That won’t work. It could be that your phone is in just the right spot to transmit through the antenna cable of your car or its wiring. But since it is only the frequencies between 95 and 97, it is probably not a huge concern. FCC regulations allow for a certain amount of intended and unintended emissions within certain limits. And as for the radio it is doing its job which is to pick up signals. 

This is just one of those quirks of living in the electronic age. Electronic devices overlap, and sometimes the result is not what was intended. Any privacy that existed was gone but the time the internet became popular, so there is little to be concerned about anymore. 

The phenomenon of leaked magnetic waves was first addressed during WW2

Leaking electronics is nothing new. The phenomenon of leaked magnetic waves was first addressed during WW2. It was enough of a problem that there is a codename for it: Tempest. Today we want our phones to connect to car audio systems, just not unintentionally. After all, if you’re listening to your favorite music and you start hearing a message a friend left you last week that’s not how you intended your phone to work.