Check phone volume up, volume down and power buttons with guided actions and supported key detection.
Play sound at a comfortable volume. Press volume up and down separately and confirm the change you hear. Briefly press power to sleep and wake the screen.
Some browsers expose volume key events; many do not. A key event is a narrow observation and does not prove the sound changed. The power-button check is manual.
Disconnect external keyboards and headsets. Never hold buttons or trigger emergency SOS as a test.
Results are saved only in this browser for up to 24 hours. This single test does not replace a complete used-phone inspection.
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