Does your mac detect the controlled without starting Serato ? Check if you have the option to play your system sounds through the 8000. This step is just way to ascertain that the 8000 sound card USB works.
If thats ok then trt starting Serato after connecting and powering on the 8000
Also try to delete old midi configurations in your mac midi utility
I too am experiencing this, on macOS Sierra, only after upgrading Serato to 1.9.10. Downgrading SDJ versions has not remedied the matter.
I’ve removed all MIDI profiles and any trace of Serato I could find, yet am still receiving the Error: Failed To Connect Audio! error when launching SDJ. The frustrating part is there is a brief second where the controller is recognized (I see four decks) and then boom, error.
The even more frustrating part is that this is not an issue with SDJ 1.9.10 on Windows 7, which works splendidly. Isn’t it Macs that are supposed to work without asking questions??
For the record, after upgrading to 1.9.10 Serato (on Mac), I receive this error — even after downgrading to an older SDJ version (1.9.x). I’ve followed all the directives as far as removing and readding MIDI devices goes, and still no dice. Am toying with the idea of upgrading but would rather not go to High Sierra for work-related reasons. Why doesn’t this work with Sierra? 1.9.10 works fine on my Win 7 Pro box.