Sony SMP-N100 Wireless Issue

I've got an issue with my Serviio and Sony SMP-N100:

Server running WinXP SP3 & 6.1 release
Sony SMP-N100
Netgear N150 Router
Cisco Gigabit switch

When wired Sony device work perfectly, Wireless works for 40-45 minutes then loses connection to Serviio ONLY.
I have to reboot the sony device to get it to recognise the Serviio Server again.
This happens wether the unit is 5 feet from the router or in another room.

All pc's, xbox360, Serviio had hardcoded IP addresses (192.168.X.X), firewall Disabled on internal network.
All other Sony SMP-N100 apps work flawlessly (i.e Nexflix, Hulu, Pandora etc), it's not the wireless network.

I've read all the posts, setup profiles, bound IP addresses on both Serviio & router.....ideas??

I just setup loggin and hope that gives me some info.

Ideas????

[Illico]

Check Sony energy saving features (auto power off, scren saver,etc ), try disabling all features.