Lose LAN connection every few minutes

[KaiserSose81]

Hi all,
I've ubuntu 11.10 ... since a month I noticed a very strange problem: I lose my LAN connectivity every few minutes (from 5 to 10). Internet still works but any connection to my subnet get lost.

I have 5 pc in LAN, there's a Router (Netgear wnr 3500 l), and If I'm connected to them using Samba/VNC/Teamviewer or whatever it's like the connection is freezed. I have to stop/start network services to get connectivity back (actually I disconnect and reconnect using the top-right network icon).
The connection from all computers to the router is wired. The computers I connect to have Windows installed.
Any Idea of what could be and how to solve? I'm sure it's not a LAN card problem since I have two and I've tried with both.

Regards,
Carlo

[KaiserSose81]

I found ... it's not concerned with Ubuntu but with the router.

goo.gl/BXDIO

Regards,
Carlo