All the functions I have tried have worked without a hitch

Although, I wonder whether Yamaha developers could, too, for example by getting the WXC-50 to retrieve the album artwork from the audio file directly at the moment when the audio file is being loaded for playback, but then that may be a question of the DLNA Application Programming Interface available functions, and perhaps any performance considerations.

The hardware is good and functions properly but they have tied it's capable hands