Fix One Speaker Not Working

Run the left and right audio test and play each side separately. For earbuds, see also one earbud not working.

Windows 11: Settings → System → Sound → choose the output → make the Left and Right channel sliders equal. Windows 10: Control Panel → Sound → device → Properties → Levels → Balance. Android: Accessibility → Audio balance; iPhone: Accessibility → Audio & Visual → Balance. macOS: Sound → Output → Balance slider centred.

Windows Settings → Accessibility → Audio → Mono audio; iOS/Android accessibility → Mono audio.

Swap left and right cables at the amplifier: if the problem moves, the source or cable is at fault; if it stays, the speaker is.

Re-pair, reset both buds to factory settings and clean the charging contacts.

Disable audio enhancements and update or roll back the audio driver.

If one driver is silent on all devices, it may be blown; check for rattling or a burnt smell.

• Speaker Test
• Stereo Test

Quick diagnosis

Balance, mono, cables, then hardware.

Test with a different source

Another phone or laptop isolates the device.

Advanced checks

Driver reinstall, BIOS audio settings, amplifier channel swap.

• Check the operating system balance slider.
• Inspect the speaker: torn cone, loose terminal or blown tweeter.
• Swap cables and amplifier channels to isolate the fault.
• Test with the stereo test after each change.