Self-install not working

The wifi works fine, but not the TV.  I get the welcome screen, then the same useless message telling me to check that all my cables are tight and to restart the TV box.  No help on the website-- it just refers me to the same installation instructions over and over again.  The cables are as tight as I'm physically capable of making them (and are apparently tight enough for the router...)   I've lost track of how many times I've tried their "solution" over the last 3 days.  Dozens.  Per day.  Since the company doesn't do installations  or provide any kind of service on site anymore do I have any options other than just cancelling the service and changing my account to Internet only?