"!playtime minutes (!filesize)" not translated

In the file audio_theme.inc the string "!playtime minutes (!filesize)" is not translated. I'm translating the string 'minutes' to my local string.

function theme_audio_format_filelength($fileinfo) {
  $format = !empty($fileinfo['playtime']) ? '@playtime minutes (@filesize)' : '@filesize';
  $args = array('@playtime' => check_plain($fileinfo['playtime']), '@filesize' => format_size($fileinfo['filesize'])); 
  return strtr($format, $args);
}