I often watch videos on my XBox 360 from a flash drive. However, the Xbox does not recognize SRT subtitles. I have figured out how to hardcode SRT files to MP4 and WMV using Wondershare Video Converter, but it doesn't seem to be a way to limit the subtitles to the part of the movie that is in a language other than English. Is there any program that can do this on a Mac?