HDMI ARC Input Messes up CAT5 Receiver on Leaf?

[txfanatic]

This is a follow up to this thread - 

 

But I wanted to separate it out from this because this is a specific question regarding the HDMI ARC input on tvs.

Ok, so here is a question for the experts...this might be the only thing that might be locking up those Cat5 receivers for my 4x4 Leaf HDMI (L44 model).  The 80" tv that is locking up has been connected via its HDMI 1 input which is a HDMI ARC input, while the upstairs tv is connected on a normal HDMI input.  I've somehow got the system to unlock, but considering this Leaf system is very finicky, would having an audio return signal back into the the Cat5 receiver potentially cause only the 80" tv receiver to lock while still maintaining full operation upstairs?  I don't really understand the 2 way nature of HDMI, but the HDMI input on the 80" tv hasn't changed between all 3 matrices that I have received (and I know all the Cat5 receivers work well because i have swapped them out).  Is the normal install pattern not very relevant to which HDMI port one attaches these Cat5 receivers?

I spent time reading both Sharp 60" and 80" tvs' instruction manuals and that was really the big difference (also the 80" has 3D and 240 hertz vs no 3D and 120 hertz for the 60" tv...btw, does that 2 way communicate as well?)

Thank you in advance