From the Focusrite website:
Scarlett 2i2, Scarlett 2i4, Scarlett Solo
Works with El Capitan? YES
Points of note: If you experience any problems selecting your Scarlett as an input or output device on your Mac, please see this article. Scarletts will only work with Cubase 8 when both the interface and the DAW are set to either 44.1kHz or 48kHz before opening Cubase. If either (or both) are set to 88.2kHz or 96kHz, the Scarletts will be selectable, but no audio will pass into or out from the DAW. We are working with Steinberg to resolve this issue and hope to have a resolution shortly.
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