May depend on what the input source is for zone 2, if an hdmi source it wouldn't surprise me at all that it wouldn't pass signal. If your rca cables (the splitter or regular male to male version) are functional that's more important/relevant. I still think your sub and the avr output is fine, you just need to adjust for the differences with the old htib "sub" (sorry, a 6.5" driver doesn't equate to "sub" for me at all).
I bet you're right, it probably has something to do with me running HDMI. I use HDMI into the receiver from my PS4 and then HDMI out to my monitor via HDMI ARC
I agree on the 6.5 "subwoofer". After messing with this a bit more today, I think everything is working fine. Its weird because that little 6.5 driver was real, I guess boomy would be the word. Had a very hollow resonating type bass. But it would move air at a very rapid pace from the port. That little thing would move way more air than this new 10 does from its port. This new sub is very subtle I guess is how I would describe it. Like for instance if you're playing a game or watching a movie, you may not "hear" the new sub, but you can kind of feel it. I have the gain at about 50%. But you almost don't realize its working. But if you go and turn the gain to 0, its really obvious when its gone. Hard to describe, but you probably know what I'm saying. Hopefully that's how a good sub is SUPPOSED to compliment your AV setup. Maybe?
I am however going to have to reposition it I think. It backs to a wall, but right next to that wall is a hall way and most of my hard hitting bass when listening to music is technically behind the sub while standing in that hallway which means its not technically in the room where the AV equipment is.