Quoted from Matrox's own support forum (
http://bit.ly/9nwpqQ ) :
To all MXO2 MAC users,
If you are experiencing corrupted audio playback when scrubbing in Final Cut Pro, please download the new 2.0 software driver specific to your MXO2 product from our Download page: http://www.matrox.com/video/en/support/downloads/. The new 2.0 build (2.0.0.0150) replaces the previously released 2.0 driver.
Once you download the new 2.0 driver for your specific MXO2 Mac product, uninstall the MXO2 2.0 software that is currently installed on your system, and install the new 2.0 driver.
Best Regards,
Matrox Technical Support