Hi PaulieB,
to CF
Not sure if it works with STBs the way it does with Cable Modems, but you should try the following:
Turn the STB off and unplug it from the power outlet.
Turn off Your Router and unplug it from the power outlet.
Turn off your PCs (shut them down completely).
Leave for a couple of minutes.
Turn the STB back on and leave it to settle and go through the bootup process completely.
Turn the router back on and leave it to settle.
Turn on the wired PC and leave it to settle.
Log in to the PC.
Test internet connection.
Turn on wireless PC and leave it to settle.
Log in to the PC.
Test internet connection.