Unable to stream 192kHz on DSM 5

[beckphotonik]

Is your switch a Netgear ProSafe model, can you tweak the port configuration from a Windows PC? if you can, then make sure the ports for the NAS and the streamer are set for high priority and restrict the data rate of the streamer port to 100Mbit ( or thereabouts). It seems like you need to force flow control between the NAS and streamer for 24/192 (and probably DSD64).
I needed to do this on my latest system but the "culprit" was the streamer not DSM5.