If audio signals cannot be sent or received between the DUAL CUBE BASS LX and an iOS device (iPad/iPhone) connected via USB, check the following points.
Specifying the USB driver
To send and receive USB audio between the DUAL CUBE BASS LX and an iOS device, the standard OS USB driver must be used. Set the [AMP TYPE] knob to "FLAT," and turn on the power while holding down the [MEMORY] button.
USB cable
Use a USB cable that supports data transfer. Audio signals cannot be sent or received if the USB cable does not support data transfer or is malfunctioning. Try using a different USB cable.
Audio settings (if the audio from the DUAL CUBE BASS LX cannot be heard on the iOS device)
When using the standard OS USB driver, effects are applied to the INPUT audio that is output. Check whether the GAIN, VOLUME, and EQUALIZER settings have been turned down.