Getting your audio interface to live under El Capitan can be quite difficult. Just last week I’ve struggled to get my Focusrite VRM Box up & running with El Capitan. Today I’ve updated my Mac to OS X 10.11.5 and suddenly my Alesis IO 26 wasn’t recognized as audio device. If you have the same issue here’s what resolved it for me:

  • Power down your mac
  • Reboot into recovery and run csrutil disable in terminal
  • Reboot and install drivers
  • Reboot
  • Voila

If you’ve had the drivers installed previously and reenabled SIP afterwards (as I have) disabling SIP fixes the issue. Unfortunately you need to leave SIP disabled. I’m not too happy about it but I’m afraid that’s all I can do until I buy a new interface.