Hey, guys. Here's what's up: I have a bunch of Matroska videos that I'd like to convert to .mp4 so I can stream them from my iMac to my Xbox 360. Quicktime is my favorite conversion software, as I've tried a whole slew of programs. My problem is that the passthrough option in the video export settings is greyed out for certain .mkv files. I've noticed that the .mkv files that don't support the passthrough option are not true 720p or 1080p resolutions, they have strange dimensions. I'm wondering if this is the problem? If so, I'd really appreciate some help on how to fix this! Thanks in advance.