These audio converters convert S/PDIF and/or Toslink digital audio to and from unbalanced stereo line-level or between S/PDIF and Toslink digital formats. The decoders take an HDMI video signal with embedded audio, pass the HDMI to an output to feed a display and decode the embedded audio to give analogue surround and S/PDIF or Toslink decoded outputs to feed equipment such as audio receivers.