Ideally you should use the usb cable that comes with your midi device. The cable that is used to connect your midi device should be designed for data use and should not be a usb "charging" cable or an unscreened cable. We would also recommend not using an excessively short or long usb cable. Something around 1.5m should be fine. If you are experiencing problems with your USB MIDI controller connected to the iTrack Dock please try different USB cables to see if this resolves the issue.
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