first of all, update RND synth to its latest firmware version here.

select WASAPI (Windows Audio Session API) as your audio driver: RND synth shows up as an audio interface with its four inputs.

if your daw doesn’t support WASAPI (Ableton Live and FL Studio, for example), select ASIO as the audio driver and use FlexASIO or ASIO4ALL: RND synth can then be selected in their configuration panel.

in some very rare cases, the booting of the RND synth was a bit too long in its first firmware version, and the computer interpreted that lack of response as a non-recognized device, that's why you couldn't interact with it.

to solve this problem, you can update RND synth to its latest version, available here.

this will fix the booting, some compatibility issues with different OS and machines, and upgrade its stability.

this is possible only on Mac.

create an aggregate device in audio MIDI setup: it combines RND synth and your audio interface into a single device for your daw.

→  open Applications → Utilities → Audio MIDI Setup

→  in the Audio Devices window, click “+” (bottom left) → Create Aggregate Device

→  tick RND synth and your audio interface, and choose one as the clock source (usually your main interface)

→  in your daw, select this aggregate device as the audio input and output

your daw now sees the four usb audio tracks of RND synth and the inputs and outputs of your interface as one device, so you can record RND synth alongside microphones, instruments, and so on.

one thing to know: usb audio from RND synth and from your interface can have different clocking and latency, so check synchronization and input numbering in your daw.

this is normal.

the usb-c port sends four mono tracks, one per instrument, before the reverb. we made this choice so you get dry signals and can fine-tune your effects in your daw.

only the minijack output carries the built-in reverb and the stereo panning.

this usually comes from a sample rate mismatch between your daw and RND synth, causing signal loss or noise. the easiest fix is to update to firmware v1.3, which improves compatibility with your daw configuration: updater.cymaforma.com

if the problem persists on Mac, open Terminal and enter this command to reset the audio driver:

sudo killall coreaudiod

RND synth follows a 2 ppqn analog clock.

if the device sending the clock uses 4 ppqn, RND synth plays at twice the tempo; at 1 ppqn, half the tempo. set your clock source to 2 ppqn.

you can’t: the trs port is midi input only (as all trs midi ports are).

the usb-c port is the only midi output.

depending on the situation, this can be expected.

→  cc 91 sets the reverb level. audio over usb is pre-reverb, so cc 91 has no effect on it. listen through the minijack output to hear the change.

→  cc 9 selects the scale. RND synth can play notes that belong to several scales at once, so switching from one scale to another can seem to change nothing. select a scale that doesn’t contain those notes, and you’ll hear them move.

another trap: some notes come from modulation, not from the sequencer, and modulation doesn’t follow scales.