The Tv stations transmissions at your location are Very Strong. So there is problems with the distribution system. Check ALL Connections , look inside the connectors on the ends of the coax and see if the outer foil shield / shield wires are pushed in toward the center conductor wire , the center conductor wire is wire that carries the signal. Also look and see if metal shavings/flakes are on the foam that is in between the center wire and the outer metal foil shield and shield wires. I recommend removing ALL amplifiers parts , the power supply , any power injectors , any and all amplifiers. I recommend connecting a known to be good coax from a known to be good matching transformer at the antenna and a known to be good antenna - connected direct to one Tv. Point the outside Tv antenna at about 150 degrees magnetic compass , here is how to point Tv antennas ,
http://www.kyes.com/antenna/pointing/pointing.html . Only use a 2 way splitter for the two Tv's in the house , do not use a 3 way splitter , 4 way splitter or more splitters , every time a split takes place the signal is reduced.