I only know that the above does not happen when I play you tube music or BBC iplayer running in IE metro version to the Panasonic sh-all1c only media monkey metro version.

Play To uses WMP not MediaMonkey, thus this is a Windows/WMP issue.

When I use playto in windows 8.1 or use charms menu Play and select DLNA player using MM8, it resets the volume to zero and therefore no sound and no way to increase it. This does not happen with Yamaha AVR or Pioneer SMA wifi speaker. The player is Panasonic SH-ALL1C with latest firmware and uses Qualcomm Allplay and DLNA. Problem does not happen in desktop MM and plays to that receiver with no volume reset.

I have to use Panasonic app or Spotify connect to set volume off zero.