In the computer world there are different kinds of line ending characters. Windows uses other characters than iOS. Stage Traxx tries to make the line endings uniform but I guess in your case this conversion somehow failed. If it happens again, make a database only backup of your songs and send it to me. I can then take a look if I can reproduce it.
It might be possible that this could also be fixed automatically by creating a database only backup and restoring it. That would be a convenient way to fix all songs in one go, but I'm not sure it will work.