Open your app folder, locate the Cubase app, select it. Press comand-i and select the rosetta mode in the window that will open. Go to the same place to change it back to silicon mode (but untick the rosetta option).
Open your app folder, locate the Cubase app, select it. Press comand-i and select the rosetta mode in the window that will open. Go to the same place to change it back to silicon mode (but untick the rosetta option).