We have a DP 34 switch which is giving us error messages all the time. We have now lost our local channels and are only getting satellite 119, never 105 or 110. Had 129 for a while and everything was fine. Now, not fine any more and no 129 on the second feed. Can you buy new switches if that is the problem? I am totally unknowledgeable about this stuff. Also, when the technicians come out is there a charge? My husband is an electrician and pretty savvy so we were wondering if we could do it ourselves. Any thoughts?