Headphones Only One Side

A 3.5 mm plug that is not fully inserted, or a phone case blocking it, connects only one channel. Remove the case and push firmly. Clean lint out of the jack with a dry wooden toothpick or compressed air.

Look for a balance slider (Windows output properties → Levels → Balance; macOS Sound → Output; phone accessibility settings). Also make sure Mono Audio is off. Then run the balance test.

Play pink noise and gently flex the cable near the plug and near the earcup. If the dead side crackles in and out, the wire is broken there. Many headphones have a detachable cable that can be replaced cheaply.

Plug into a different phone or computer. If the problem follows the headphones, the fault is in them; if not, it is the jack or settings of the first device.

Unpair and re-pair. Charge both sides fully. For true wireless earbuds, see one earbud not working.

Earwax can block the mesh over an earbud driver, making one side quiet or muffled. Remove the tip and clean the mesh gently with a dry soft brush.

If one side is silent on every device with a known-good cable, the driver or its internal wire is damaged. Check the warranty before opening the housing.

• Stereo Test
• Headphone Test
• Balance Test