Xiaomi HyperOS disconnects the USB endoscope when the screen sleeps

On some Xiaomi phones running HyperOS, a USB endoscope that was connected and working disconnects the moment the screen turns off — locking the phone, letting it time out, or pressing the power button all trigger it. The probe is not failing: Xiaomi’s charging and power-saving policy is changing the USB port’s role out from under it.

Why HyperOS drops the connection

Xiaomi’s charger policy on HyperOS ties the USB-C port’s role to whether the screen is on. Phone logs captured during testing show that with the screen off, the policy selects sink-only mode — the mode a phone uses to receive power, not supply it — and cuts power to whatever is plugged into the port. A probe with no power cannot stay enumerated, so Android and Magic Endoscope both see it as disconnected, even though the physical connection never moved. This is a phone-side power policy, not a probe defect, so check your probe in the compatibility list only if detection is unreliable even with the screen kept on.

We confirmed this on a Redmi phone running HyperOS 1.0 on Android 14. Because it comes from a charging policy rather than something specific to one model, it likely affects other Xiaomi, Redmi, and POCO phones on HyperOS too, though exact timing can vary by model and HyperOS version. It is separate from the manual OTG switch some of the same phones also have — see USB endoscope not detected? Check the OTG switch if the probe won’t connect in the first place, rather than dropping mid-inspection.

Keep the connection alive

1. Keep the screen on for the length of the inspection. Set Settings → Display → Screen timeout to its longest option, or disable auto-lock, before you start.
2. If the screen does turn off or the phone locks, unplug and firmly reconnect the probe once the screen is back on, then reopen the connect screen in Magic Endoscope. Whether the port recovers on its own once the screen wakes is not consistent across phones, so a re-plug is the dependable fix.
3. Confirm the OTG switch is also on before you start (Settings → Additional settings → OTG on Xiaomi, Redmi, and POCO phones). It is a separate setting from the screen-power behavior above, and both need to be satisfied.
4. If the picture also drops within the first few seconds of every connection, regardless of screen state, that points to a different cause — a cable, adapter, or capture mode rather than the behavior on this page. See the USB endoscope setup guide for that checklist.

Confirm it’s fixed

Keep the screen on and run the probe through a normal inspection length for your job. Then lock the phone once, on purpose, and check whether Magic Endoscope recovers the picture on its own after you unlock and reopen the app, or needs a re-plug — knowing which one your phone does saves time on the next job. Save a test photo or video from a session that survived a screen lock, and check it in the gallery.

If it keeps disconnecting

Send product support your exact phone model, Android and HyperOS version (Settings → About phone), probe model, and connection type. Note how long the picture lasted before it dropped, and whether it happened only when the screen turned off or also while the screen stayed on — that distinction separates this report from a cable or bandwidth issue.