Mine works fine. I'm also running a Mac. Here's what I did: Used a USB drive formatted to FAT32. Put my movies in the root folder. I used MP4 format and kept my resolution to usually 480X320, however a few at 640X480 also play fine. When you insert the USB drive you have to start pushing the Media button on the radio until you cycle through to the video screen. There will be a large Browse icon on the left side of the screen. Tap the Browse button until a list of films shows up and tap the one you want to watch. I was actually surprised it worked so smoothly because they told me at the dealer that it was impossible to watch video on it.
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