Clicking any link reloads page I was on

It seems as if something is taking over the browser, when I click on a link, it often, but not always, reloads the page I’m on.

EG.
Google
Enter “Something” in the Search box
A list of links with “Something” in them appears
Click on a link
The Google search page appears agian

This happens on the workstations, not on the gateway machine. BUT, it only started recently.

Virus scans come up clean.

Browsers: All (Mozzilla, Netscape, IE)
Network: TCP/IP
Proxy server fpr Internet access: PPPshar on the gateway machine