N7700 networked folder and video playback problems

I have set up some network drives from folders on the NAS.
The box is configured with 7 WD10EADS in one big Raid6 with Ext3 file system.

When I try to play videos directly there seem to be serious trouble with loss of frames.
At the same time as the freeze or drop of frames during playback I can hear the disks work for a second. The files are using Matroska which is quite common for a lot of high quality streams, but these videos are not. Playback of any video directly from a networked folder with VLC seem to have issues. Basically VLC reports around 5% loss of buffers and frames.
Tried using WMP with ffmpeg for some xvid and that seem to work ok.

There is nothing wrong with my network as I can play back the same files from a networked disk on another pc without any issues.

Anyone know whats going on? This can't be normal

Dear Sir,

If possiblw would you please provide some sample file for us to duplicate this issue?

Hi Yvon,

Unfortunately I don't think giving you a file would be legal ;)

Further testing showed that increasing buffer for file playback in VLC from 500ms to 1500ms helped.
Why this is needed for the N7700 I don't know, but that's what I'll have to do if I actually keep this thing.
So far there are a few things I don't like...noise levels and absence of flac support on media server to name a couple.