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@djrhouse > Did you assign any samples to the OSC Sampler within rekordbox? If not, hitting the triggers for them on USB-A or USB-B (depending on which USB port your computer is connected to), won't play anything.
Open rekordbox, open the sampler panel, and click here:
Next, drop any sample (or song) to the slots so when you press the corresponding button on the controller, it will play:
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