Last content source is unavailble

I have a NAS WD Hardrive that has all my media on it.  I have 5 WDTV live units that access it.  They will play fine, but at random times they loose connection and cant see the hard drive anymore.  and the last content error comes up, I look for the drive once, no drive, look again there it is and I can get right back in…

Why is this doing it? Am I missing a setting…

It is finding it via server…  the nas has tmonkey…

Anything I need to do special when hooking up multiple units?  they are all connecting wirelessly.  I think they are messing with the access point as I have to now reboot that from time to time too…? any ideas?

and I did rename them all a different name… wdtvlive1, wdtvlive2, etc…