The INSTRUMENT 1 can be played expressively by using the fingerboard and bridge in different ways. In order to allow these techniques to work with third-party sound generators, the INSTRUMENT 1 sends polyphonic expression data on multiple MIDI channels. You can adjust the settings in your software depending on how you want MIDI data to be received.
Setting your software to receive six channels should ensure that strum and bow modes work properly. When the INSTRUMENT 1 is set to Multi-Channel MIDI mode, the channels 2-7 are used for the played notes while channel one is reserved as MIDI base channel.
The Mac, PC, iOS apps allow to set the INSTRUMENT 1 to multi-channel MIDI mode.
When the third-party sound generator is set to a multi-channel MIDI mode, ensure that MIDI channels 2-7 are set. This setting might be labeled multi-channel, MIDI-mono mode, MPE, or similar.
Note that some sound generators do not support a multi-channel MIDI mode. In this case, the INSTRUMENT 1 can be switched to Single Channel MIDI mode so that expressive data (such as pitch bend when sliding) is still used only for the last note that was played. In single channel MIDI mode, the INSTRUMENT 1 sends MIDI on channel 1.
If fretless modes and pressure are not used, third-party generator can be set to omni, where all MIDI channels are received. In this case, using pitch bend and expression for more than one note at a time can cause problems.