Hi Christian,
the Retrokit Midi Cable is a Smart MIDI cable, with a Firmware to control the Volca Sample 1 or 2 from a single MIDI-channel.
So the Volce is only on Midi Channel 1, thats all. No,the error happens suddendly,
and i dont know why. Sometimes when I mute for example a drum and sometimes when the Zaquencer is just running.
Markus