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Describing your hardware set-up
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When starting out with Reaper, one of the challenges can be getting everything connected.
To help us help you, it would be valuable if you can sketch out what set-up you have in mind, showing the paths for audio and MIDI between the various units. Otherwise we could only be guessing and go off down the wrong track.
Also, please post (or attach) screenshots of the Audio and MIDI device configurations that you have set up in Reaper's Preferences, showing the drop-down lists for the audio. Click [Options] > Preferences > Audio > Device, and MIDI Devices.
Don't post them here, put them in your own thread.
Below is a simple example:
With this sort of information, we are much better placed to offer guidance.
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