Headphone output makes no sound.

• Make sure the headphones are fully inserted into the jack and that the connection is secure.
• Check that the Fosi Audio is selected as the default audio output device on your computer or device.
• Try adjusting the volume levels on both the DAC and your computer or device.
• Try using different audio sources and input methods to see if the problem persists.
• Test with a different power/data cable.
• Try using different headphones and a 3.5mm jack cable. (If the DAC comes with a Headset Microphone Two-in-one Adapter cable, replace with another splitter cable)
• Test the other output methods (such as RCA out) to see if the issue is specific to the headphone jack.

If you have any questions or concerns, please don't hesitate to contact support@fosiaudio.com.