Belkin G+ Mimo Lag Problem

I've one PC upstairs linked wirelessly to a Belkin G+ Mimo router downstair with a Belkin USB Adapter. Connection and strength seem fine but getting a lag every 30 secs or so.

Ping Stats
Packets sent = 464, Received = 464, lost = 0
Min = 1ms, Max 2002 ms, Average = 41 ms

it basically stays at 1 or 2 ms then spike to 1000 plus, then back to normal.

Windows Zero config is disabled.
Any one with any ideas as to why and how to fix?

thanks for the reply..

on the plus side, i finally cracked it over the weekend, it was the Belkin wireless receiver software checking the network every 30 secs.

why it never ocurred to me earlier i don't know, it was for the same reason i disabled the WZC...