Check if you still have the 'reroute MIDI to DXi' box checked. If you chose the USB out, and shut off the thru on that USB device, this *may* prevent the MIDI from reaching the soundsource (which would be a softsynth)via MIDI in. This would explain the sound stopping when thru is disabled in the SD-35. Otherwise I don't understand how shutting down MIDI thru on the SD-35 would result in no sound. How are you monitoring (listening to) the SD-35? Unless you have connected the 'audio outputs' of the SD-35 to a mixer or speakers, you are not hearing it in the first place. It does not transmit audio over the MIDI connection.


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