I have an attic-mounted antenna like this
My house is wired with RG6 to several rooms and a distribution point in the attic. I've got the antenna signal split and going to 4 different receivers around my house.
I've got a good signal across all of the Austin locals and even can pull in channel 2 out of Fredericksburg (and channel 14 here in Austin with one of my receivers).
I'm experiencing an issue with reception on channel 42 and channel 7 on my TiVo Premier receiver in the living room. Today while it's been overcast, for example, channel 42 has been very pixellated and breaking up on that receiver, though it's still at a very strong signal level and perfectly watchable on other receivers in the other room. Yesterday on a clear day it was no issue. I've also noticed that at night I'll have breaking up problems with 42 and with 7, though less so on 7.
I kind of suspect that the issue is that the network of distribution I have going around the house is causing interference with these two stations. I'm using good, well-shielded cables to my receivers, though I am using a couple of two-way splitters to get signal to all of them.
Any advice on how to troubleshoot this and get a good, reliable signal to each receiver, apart from trial and error?