All:

Here is my setup:

Sony 1040 AVR - HDMI out 1 is ARC

Samsung UN75F800 - HDMI in 3 is ARC

Xfinity CableBox

In a test, I setup everything I wanted and it worked (!), including  ARC and CEC (Samsung calls it AnyNet, Sony calls it Bravia) working exactly as I wanted with ability to 1) ARC: return Samsung Apps audio to my Sony AVR 2) CEC:  eleganly control power and Sony AVR volume with my Samsung remote.

In my final local, I need to use 35 foot HDMI cable to connect Samsung TV (HDMI 3 - ARC - in) and Sony AVR (HDMI 1 - ARC - out).   I setup these cables in wall http://vericomsolutions.com/images/literature/VericomHDMIV3000Cable2012.pdf

Per first test above, I enabled Anynet/CEC on Samsung and CEC on Sony AVR.

But, I have setup everything the same using the 35 foot cables and I can't get sound from Samsung TV to return to Sony AVR and I can't get Samsung AnyNet to recognize the Sony AVR as CEC device anymore.  I can get the AVR picture (Xfinity or Blue Ray) to the Samsung TV (AVR sound) or sound and picture to Samsung Tv/speakers.

So, on a 35 foot cable, I can pass information from AVR to TV, but I can no longer the TV to pass data back to AVR, like it worked in my test with shorter cables.

Any suggestions on how to fix this?  Settings?  Boosters?  Equalizers?   What can I do to assure CEC and ARC work on these high end cables?

Note...on the 35 foot cable 1) no sound passing from TV to Samsung 2) Anynet on Samsung TV cannot find the Sony AVR receiver 

I would appreciate any help the AVS forum experts could lend!  Thanks

Mark