Trash ANY older Symphony installer packages you may have on your computer (desktop, downloads folder, etc.) Old installers can mistakenly trigger ‘firmware mismatch’ warnings.


Download the latest Symphony installer package from our website:


– Note any settings you may have made for your Symphony I/O in the Maestro software, as these settings can get reset after an update.

– Run the Symphony UN-installer included in the latest installer package. Restart your computer.

– Run the Symphony Software Installer from the latest installer package. Restart your computer.

– Plug in the Symphony I/O via USB to your Mac. If your Mac has USB 3.0, you should first try it with a USB hub (an Apple keyboard with USB ports is the best hub to use if you have one) to do the firmware update… the firmware update will not work on most USB 3.0 ports, so a hub will bring it down to USB 2.0. Note- USB Audio should work fine on USB 3.0 ports.

– Power up the Symphony I/O.

– Launch the firmware updater app from the latest installer package and update the firmware. Make sure the firmware successfully updates before proceeding to the next step. If the firmware updater gets stuck or doesn’t work, quit the firmware updater app, power off the Symphony I/O, power the Symphony I/O back on and try the update again. You may need to try different USB ports. If the updater says it ‘failed’, click ‘try again’ and run the update again. If you have multiple Symphony I/Os, make sure to update EACH of them by selecting each unit in the drop-down menu of the firmware updater (Symphony I/O 1, Symphony I/O 2, etc.) Once the update finishes, quit the updater and then relaunch it to confirm that the firmware is up to date for each unit.

– Confirm that your Symphony I/O is in the correct audio mode by pushing in and holding on the right-side front-panel encoder and scrolling through the different modes and then pushing in on the encoder again to restart the unit in the selected mode.

If you’re using Symphony I/O with Symphony64 PCIe or Symphony64 Thunderbridge:

Launch Audio MIDI Setup (Applications> Utilities> Audio MIDI Setup). We recommend using Audio MIDI Setup instead of System Preferences Sound.

Make sure that ‘Symphony64′ (PCIe or Thunderbridge) is selected in the left-side column. In the ‘Source’ menu on the right, choose the appropriate port selection depending on how many Symphony I/Os you have. If you have 1 unit, choose ‘Port 1: 32ch’… if you have 2 units, choose ‘Ports 1-2: 64Chs’. Quit Audio MIDI Setup and restart the computer.  Wait until the unit/units sync and stop clicking before launching Maestro. This can take a couple minutes if you’re using 2 Symphony I/Os.