I have actually tried several programs to split MKV files. MKVMerge is the easiest and actually works, but I've recently run into a problem with it. I'm trying to split an MKV of one of the DVDs I'm backing up (made up of 4 episodes) so I set Merge to split after 00:23:42. Instead, Merge splits after 23:46, then 23:42 and so on at random times. I read that it has something to do with frame types, but I've never had this problem before. Any help would be appreciated.