Having a file with a backtick (` ) in the name leads to

sh: 1: Syntax error: EOF in backquote substitution

This is due to the simplicistic FfmpegStreamInput/AudioStreamInput::GetCommandLine API. For secure usage, please see these explanations on stackoverflow: http://stackoverflow.com/questions/288038/how-to-safely-escape-a-string-from-c/288203#288203