Short Bluetooth range on iPhone 14?

Are you following the pairing procedures for pairing the headphones to your iPhone? Do they pair easily? Have you done a factory reset of the headphones?

It’s best to charge headphones and iPhone fully before pairing. If you want to reset the headphones here’s the steps.

Factory Reset Steps

1. Power off the headphones by pressing and holding the Power button (middle button on right earcup) until they turn off.

2. Disconnect any charger plugged in via USB, unplug it first.

3. Press and hold simultaneously the Power button and Volume down (-) button (on right earcup) for 7–10 seconds.

4. Confirm reset, blue indicator light will flash 4 times in a row; release the buttons, this means the reset is complete.

I don’t use ChatGPT, but evidently we both use the Sony instruction manual as our source. The next two steps are first to reset all settings back to factory and the second is to backup your device, erase the contents and lastly install your backup.

If the above fails, Apple Support can do diagnostics on your iPhone. If you’re within the return period on your used device you may want to consider returning it.

Apple Support can perform diagnostics on your iPhone. It can be done in person at an Apple Retail Store or at an Apple Authorized Service Provider. You can also contact Apple Support and request remote diagnostics.

If you’re in the US, please call  1-800-MY-APPLE, or outside the US, consult the support articles below. In Canada, call 1-800-263-3394.

Contact Apple for support and service - Apple Support

Genius Bar Reservation and Apple Support Options - Apple

Explore Service Locations

Official Apple Support

It’s likely the Sony WH-CH520 isn’t actually disconnecting—it’s just auto-switching between devices (iPhone, iPad, Mac).

To stop this, Forget the headphones on your iPhone and re-pair them. Then do the same on every device where the WH-CH520 has ever been paired. This resets the switching behavior and prevents the device-hopping chaos.

Forgetting a device on an iPhone means removing its pairing and connection information from the device's memory. When you pair certain devices, like Bluetooth headphones, speakers, or other accessories, your iPhone stores the connection details to make it easy to reconnect in the future.

When you "forget" a device, you are essentially erasing that pairing information from your iPhone. As a result, the device will no longer be recognized, and your iPhone won't automatically connect to it when it's in range.

After forgetting a device, if you want to use it again in the future, you'll need to put the device into pairing mode and re-establish the connection by going through the pairing process on your iPhone.

Watch the GIF below

Bluetooth interference can potentially cause connectivity issues due to the disruption of the wireless communication between devices. Bluetooth operates in the 2.4 GHz frequency range, which is also used by various other devices such as Wi-Fi routers, microwaves, cordless phones, and even some baby monitors. When multiple devices are operating nearby and using the same frequency band, interference can occur.

Hi, Airdrop uses both Bluetooth and WiFi. BT is used to find nearby devices and the actual data is transferred via WiFi. The spec for older BT devices is around 35 ft or 10m.

Is your iPhone updated to the current version of iOS, iOS 26.2? Is the firmware on the headphones updated to the latest version?

No idea what you mean by "an official second hand reseller".

Take it back and get your money back then go buy a phone from an actual authorized retailer or directly from Apple

ios 26