Mozzi puts out audio on pin 9. Dzlonline synth software uses pin 11. The following circuit automatically connects the pin producing the audio to the audio out through a resistor. The other resistor will be connected to a pin configured as an input and should have no effect in the audio.

With this little mod, either synthesizer software can be loaded and it will work without modifying or reconfiguring the board.

A simpler modification for the existing board. The output impedance will not be the same for both synthesizers, but it will work as a quick and dirty hack.

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