Let’s say you have an MKV movie, and that movie also has a SRT (subtitle) file. BSPlayer will automatically use the SRT file in the folder with the movie. If the SRT file has the same name (without extension) as the MKV movie, that SRT file will always be used. How do you use another subtitle with the movie? One solution is to drag & drop the subtitle over the BSPlayer window, or to load another subtitle. But if you watch the movie with breaks, that would be rather inconvenient. If you can’t delete the SRT file, for whatever reasons, how can you override loading that subtitle? The answer is simple, although it might be a bit unexpected – rename the file you want to be used as [nameoftheMKVmovie].[sub extension]. So, just use the same name as the movie + SRT file into a SUB file, and add .sub at the end of the filename. That subtitle will always override the SRT file.