WAV files not visible on XBMC UPnP server (from Mac)

I've got XBMC running on OSX Mountain Lion, and am using it to stream music to a Sony BDP-S580, which is DNLA / UPnP enabled. The Sony device sees AAC and MP3 files in my XBMC library. However it doesn't see any of my WAV files.

I've confirmed that the Sony device can see and play WAV files when they are on a USB drive that is connected to it, and I've confirmed that the WAVs are actually in my XBMC library, and that my Mac will play the WAV files using XBMC. So the problem appears to be that the UPnP server isn't making them available to the Sony.

Any ideas how I can fix this? My assumption is that the problem is user error, not with XBMC, though if others can confirm that XBMC for OSX isn't serving WAVs then I'll file a bug report.

Many thanks for your time.

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Edit: I should have said that my Sony device doesn't see any hi-res (i.e 24 bit / 96 and 192 kHz) WAV files on the XBMC UPnP server. I don't have any 16/44.1 WAVs in my music library, although I'll downsample some of my hi-res WAVs to test out whether the issue is one of streaming hi-res files over the network. I don't know why this would be a problem (XBMC has no problem playing h-res WAVs on my Mac), but you never know.