hey ducky, did you sort this out? I have a Linn Akurate DS with the same issue and the same NAS. Im using a Thecus PRO 5200 and the UPNP software is junk!

All my mp3 files work fine, all wavs work fine but some FLACs just dont play at all.

Im using Tversity on my PC with a map to the Thecus, Twonky on the Thecus is self is terrible..

Ive ordered a N800 and just wondering how its going? please dorp me an email or PM if you can

Thanksl
das