WF-1000X turns off automatically when using Headphones Connect app on iOS device
This symptom can be fixed by updating the firmware update.
For details on Firmware update, refer to the following page:
Firmware update 1.0.7 for WF-1000X
NOTE: In the case of iPhones, iPads, or other Bluetooth AAC codec-compatible devices, it is recommended that you always use in Priority on sound quality mode.