Has the Hopper w/sling ever been connected to the wireless...? Even tho the hopper has a network cable hard lined to the router it might still be producing two IP addresses which causes lots of congestion on the hole home network.
If you go to the wireless setup, enter in the wrong password and save the changes made this will hopefully resolve your issue.
If you go to the wireless setup, enter in the wrong password and save the changes made this will hopefully resolve your issue.