try changing modulator setup from air 60 to cable ch73 you may have to select the cable option on your tv if the channels dont go that high.try an attenuator,,, little thing in video/auidio cable package that came with reciever, it says ATTENTION on it....hook that to back of reviever tv 2 output... check connections... if there are crimp on ends, and not compression fitting, that may be the cause, also check if there are splices in the line, that a blue dielectric barrel was used...that tech should not have left with that poor of PQ.,,,