Only basic Channels (ABC, NBC FOX etc.) found on channel scan with HD Homerun Prime, MTR700 adapter and cable card installed and pared

I have a HD Homerun Prime with a Cox Motorola MTR700 and Cable card set up that I use with my computer to watch and record TV. This had been working fine for years and then a year ago I started losing video on some channels, SYFY, FX . The audio still worked and recorded but no picture. After a couple days I lost more channels completely and then suddenly I could only get the commercial channels (ABC etc.).. My Homerun showed the channels but nothing was on them. I re scanned and only got channels 2,3,4,6,7,10,13,14,15,20,46,47,47,49,60,109,and 8 or 9 oldies channels plus the 1000 equivalents (1004, 1006, 1013 etc.I called cox and talked to a tech. They had me go to the cox store and exchange the Cable card and adapter for new ones. I did, called and paired the two and still the same problem. I did this 2 more times and then they sent a tech out and he  swapped out 2 more sets of card and adapter. Same results as before. I again called cox  tech and got a voice male from a tech in Louisianan who said they thought it must be the HD Home run. I called back several times and left voice messages but no one called back. I had been in touch with Silicon Dust. while dealing with cox and they had me turn on the record/report  switch and had been monitoring and checking the Homerun Prime and every thing seemed to be working fine. All this was several months hours of phone calls and I was pretty frustrated with the whole deal. So I decided to just live  with it. Last summer I tried replacing the HD Homerun Prime and all splitters and cables but  no improvement/change. Today I discovered this Forum. Does anyone have any ideas?