Smaart IO Isn't Working Properly in OSX 10.11.4

If you are having problems with Smaart interacting with your Rational Acoustics Smaart I-O, and you are running OS X version 10.11.4 or newer, you are likely experiencing a problem with the recent OS X update.

In the 10.11.4 OS X update, the Smaart I-O is renamed internally to "Smaart I_O", which breaks the communication between the Smaart I-O and Smaart. You can verify this if the device is named "Smaart I_O" in Audio/MIDI Setup.

To resolve the problem, perform the following steps:


  • Open up the Smaart I-O Control App
  • Click Options -> Options
  • Select your Smaart I-O device 
  • Click "Rename"
  • Name the device "Smaart IO"
  • Save your changes
  • Power cycle the I-O by unplugging it, waiting a few seconds, and plugging it back in


This should resolve any issues you are having with the Smaart I-O due to the OSX update. This change only needs to be performed once and will persist even after closing Smaart.