My book live keepos dropping off network

Hi, my book live NAS is wired to my router and accessed wirelessy by my Macbook and via ethernet to wdtv live. WDTV live can always access it  but oon my Macbook Finder  wndow it shows when laptop intially turned on then disappears or is not accessible after a time. If I sleep Macbook and wake it up My book live shows again in Finder window.  I have set My book live to ‘never sleep’ in energy settings to try andd resolve this  but with no luck.

Any thoughts?  My router is the standard one supplied by Talk Talk.

If the WDTV never looses connection, then it might be a low signal problem with the router.