vnc problems on macmini

Hi folks,

I've got a mac mini in the living room as a media center that I access using RealVNC from a PC. After about 15 minutes of working fine the connection will suddenly abort, each attempt to reconnect aborts too. Then after a while it magically starts working again. Reboot of the mini doesn't seem to have an effect, it's totally random when it'll work and when it won't. I've tried using both OXSVNC and Apple Remote Desktop and the problems are the same.

Network connection is also weird, when VNC connection starts bombing I can see the mini in the Network Neighborhood but can't access it. I can't ping the mac from the PC and trying to ping the PC or the router from the mac gets a "no route to host" error.

Any help you can give would be most appreciated.