21.How to use the USB DAC function in S15?

The USB DAC function requires a connection through the USB DAC port on the front panel. The other USB ports in S15 do not support USB DAC.

Connecting S15 to Computers

[Windows PC]

1. Install FiiO USB DAC Driver

Download driver v5.68 or newer: https://forum.fiio.com/note/showNoteContent.do?id=202105191527366657910&tid=17

2. S15 Input Settings

Long-press the right knob to switch to USB DAC Mode.

Connect the S15’s front-panel Type-C USB DAC port to the PC using a USB cable.

3. S15 Output Settings

Select the desired output:

BAL.LO/LO Output(Please disable the I²S switch)

Coaxial/Optical/AES Output(Please Enable the corresponding output switch)

I²S Output(Please enable the I²S switch)

4. PC Audio Configuration

Set System Audio Output and Media Player Output to "S15".

Play music through supported software (e.g., Foobar2000).

5. Playback Tips

 How to play lossless/DSD files: https://forum.fiio.com/note/showNoteContent.do?id=202105281106126083841

[MAC]

1. No driver required. Connect S15 to MAC via USB, then select "S15" in System Preferences > Sound > Output.

2. Volume Control: Set macOS volume to max, adjust output level via S15’s knob.

Detailed setup:https://forum.fiio.com/note/showNoteContent.do?id=202105191616354037331

[Linux]

Driver-free but compatibility varies by distribution.

If unrecognized, please try alternate USB ports/cables.

Connecting S15 to Mobile Devices

[Android Phones/Players]

1. Connect S15’s USB DAC port to the Android device using an OTG adapter cable (e.g., FiiO LT-TC/LT-LT series).

2. S15 Settings:

  Long-press the right knob to switch to USB DAC Mode.

  Configure outputs as needed (see Output Settings above).

3. Play music on the Android device to enjoy high-quality audio.

Note:

1. App Settings: Enable "USB Audio Output" in your media player (some apps disable it by default).

2. Android-Specific: Activate Developer Options → Enable USB Debugging/OTG.

3. Hardware Checks:

Ensure the adapter supports OTG functionality.

Verify correct cable orientation.

4. Compatibility Note:

  Due to non-standard USB audio implementations across Android brands, full compatibility isn’t guaranteed. Please test with alternate devices or PCs to isolate issues.

  If problems persist, please contact FiiO support.

[iOS Devices (iPhone/iPad)]

1. Use an OTG adapter (e.g., FiiO LT-TC/LT-LT series).

2. Enable iOS Decoding option in S15’s USB DAC settings.

3. Play music directly from the iOS device.

Notes:

1. Requires iOS 10.0.2 or later. Lower versions are not supported.

2. Volume control could be adjusted via S15’s volume knob (The volume in iOS device is disabled).