If you have a Mac from 2015–2018 still on Mojave, follow these steps:
Run the installer from the DMG. It will fail at first – allow the "Security & Privacy" block.
Go to System Preferences → Security & Privacy → General – click "Allow" next to the Pioneer driver. Pioneer Ddj T1 Driver Mac Download
Reboot your Mac.
Connect the DDJ T1 (power supply required – USB bus power is not enough). If you have a Mac from 2015–2018 still
Open Traktor Pro 2 (or 3) – Go to Preferences → Audio Setup → Audio Device: Pioneer DDJ T1.
If the device does not appear, check Applications → Utilities → Audio MIDI Setup. You should see "Pioneer DDJ T1" as an output device. Run the installer from the DMG
Even on compatible Macs, users face issues. Here are the top three:
A: Go to /Applications/Pioneer/DDJ_T1/ and run Uninstaller.pkg.