You must have something faulty going on with your router, or your USB receiver has a problem. Did you install the updated drivers for the USB device? I would check that first.
Otherwise, does the USB receiver pick up other wireless signals and hold a connection? If it does, I suppose you must have a faulty router, though this is very strange as I personally have purchased numerous Linksys routers for customers and have had nothing but unparalleled success.
Also, you could always check the wireless configuration on the router (probably try factory defaults first to make sure). Hope this helps!
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