the subtitles are in spanish and strange symbols replace letters and sometimes it changes significant letters for squiggles, I 've searched in some forums and ran with this solution:

Quite probably those are UTF-8 files which were saved without the UTF-8 byte-order-mark.

Try opening them in a UTF-8~aware editor (EditPlus, EMEditor, BabelPad), and
re-save as compliant UTF-8 text.