https://www.guitarcenter.com/Used/Steinberg/Used-Steinberg-CC121-Audio-Interface-122025173.gc
Used Steinberg CC121 Audio Interface | Guitar Center
For greater savings check out our Used Steinberg CC121 Audio Interface and get a great deal today!
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https://ardour.org/files/doxygen/classArdourSurface_1_1CC121_1_1Button.html
Ardour: ArdourSurface::CC121::Button Class Reference
the open source cross-platform DAW
ardourbuttonclassreference