First of all I would like to start by saying that this thread is mostly about subtitle support. There is another thread here that deals with conversion of the video, audio, and pass through of both. I've tried two different methods of putting subtitles into m4v video: Burned in or permanent subtitles: 1) Used mkvextract to extract the ssa subtitle track. 2) Converted ssa subtitle track to srt subtitle track with Subtitle Workshop 3) Cleaned subtitle track with Subcleaner 4) Converted video into valid AppleTV mp4 with VisualHub. 5) Opened video in Submerge, selected appropriate srt file, rendered subtitles, saved as self contained mov, imported into iTunes, and synced to AppleTV. Where I failed: Submerge is an excellent program that rendered the subtitles correctly, but there are two fatal limitations that I don't know how to work around. It only supports 2 lines of subtitles. It won't automatically wrap subtitle lines that are too long. I had Subcleaner limit the lines to 50 characters which will wrap some lines into 3 or even 4 different lines. 65 characters can help work around this, but some dialog is still into 3 lines which Submerge still cuts off. One line that I just looked at was 145 characters long and that isn't the longest one. Soft subtitles compatible with AppleTV/iPhone with Muxo: 1) Used mkvextract to extract the ssa subtitle track. 2) Converted ssa subtitle track to srt subtitle track with Subtitle Workshop 3) Cleaned subtitle track with Subcleaner 4) (Tried with and without this step with same results) Converted the srt document to utf8 with iconv (iconv -i ascii -t utf8 fileASCII.srt > fileUTF8.srt 4) Converted video into valid AppleTV mp4 with VisualHub. 5) Opened video in Muxo, clicked + to add subtitle track, selected the track, clicked Add Track, closed the program. Where I failed: I opened all_done_subtitles_added.mp4 in Quicktime Pro without a problem, but after changing the file type to m4v so it will pick up subtitles QuickTime Pro gives the error: "The movie contains an incorrect duration." The file will open in VLC 0.9.4, but the seek bar is unusable as it tries to seek through what it thinks are thousands of minutes of content moving far too quickly. The real question: How does one actually add actual subtitle tracks from an mkv on a Mac? I have many tools that help get part of the process done, but competing the process seems impossible to do in a way that is actually readable on the screen. Please don't bother to suggest that I use QuickTime Pro + Perian to export the video directly from the MKV with subtitles read by Perian. This works at 5fps on a Late 2008 Macbook Pro and is unusable in my opinion. Final notes: I am using or have available OS X Leopard 10.5.5, QuickTime Pro, Handbrake 0.9.3 Snapshot 3 (r1797), VisualHub 1.34, Perian 1.1.2, Subtitle Workshop, Subcleaner, mkvextract, VLC 0.9.4, and other assorted tools. I am using Crossover from Codeweavers (Wine) for the Windows software so I do not have a full Windows installation available.