There is a known issue in which users, using Dual-Monitor setups on Windows 7, sometimes experience crashes if they use Mocha, when closing the plugin and going back to Avid, regardless of if ‘Cancel’ or ‘Apply’ is pressed.
In this situation, when Mocha Pro is crashing Avid on close, there are a few things you can do that should help matters. Please note, however, that these will need to be in place the entire time in order for Mocha not to crash. So, when you open Mocha and make these adjustments—even if you set everything up correctly—it will crash on Close at least one more time.
The primary things are that Mocha Pro’s interface needs to be entirely visible on a single monitor. That is:
With this, we recommend keeping the interface in a way where there’s at least 20-30 pixels on each side before it hits the edge of the monitor view. Along with that, if you bring the interface close to the top of the display, Windows will trigger the option to Maximize the window. If it does this, the problem will occur immediately, so you’ll want to make sure you avoid this at all cost.
Lastly, which monitor you choose to show Mocha will play a factor, and it might not be quite so obvious. The primary thing that will need to be in place is that both the Effect Editor and the Mocha Pro interface need to be on your primary monitor. This is not necessarily the one with the Start menu; instead, if you go into the Display portion of your Control Panel, and then into Adjust Resolution, press the ‘Identify’ button and each number will show the number “1” or “2” - the one that shows “1” is the one that both the Effect Editor and Mocha Pro interface will need to be on.