Hdmi signal degredation depending on the display?

[Ombox76]

Sup.

 

I ran 2 50foot HDMI cables through my basement ceiling.  bithHdmi works 50ft plus 2 ft extension on one side and 6 foot on the other, connected to a cheap Chinese projector from gearbest.  Once I plug it in to my LG not so flat screen flat screen, the signal no longer works unless there is no extension on either side, and even then, only one of the 2 cables work.  I am very confused on how this works, why it works, Etc.  They are both 2 way cables, and I can even send signal the other way to an Asus monitor from an Xbox using the cables, but I'm dumbfounded how it works only sometimes.  

 

Thanks for any knowledge.