If audio cannot be sent or received between the AC-22LX and an iOS device connected via USB, check the following points.
- USB cable: A malfunctioning USB cable may prevent audio from being sent or received. Try a different USB cable.
- Audio settings: When using the standard OS USB driver, effects are applied to the audio output. Check that the [VOLUME], [BASS], [MIDDLE], and [TREBLE] knobs are not turned down.
- USB driver settings: To use USB audio with an iOS device, the unit must be set to use the standard OS USB driver. Set the [AIR FEEL] knob to "XY", then turn on the power while holding down the [MEMORY] button.