FWIW, I have used HDMI over cat5E/6 with varying degrees of success. That would be one way to get the HDMI signal from receiver to (distant) HDTV using the existing cat5E cables in the wall. That said, it could potentially be easier to just locate the devices elsewhere. Something like this might help:
https://www.amazon.com/Sabrent-Extension-Extender-200-Feet-HDMI-EXTC/dp/B001PT1A7C
What would be useful though is knowing more specifics about HDTV (actual model number) and where *all* of the room/cables/connections/types are currently located and plan to be located. Are there cable/sat boxes involved, Blu ray players. Be more detailed than what you have listed above, especially regarding what rooms services enter the home and where the current jacks/ports are located. Even adding info such as 'I don't know where the speaker wires terminate in xxx room' ,etc.
I just moved into a house with built in speakers but i'm unsure how to hook everything up. The speaker wire connections are in a different room than the TV/Speakers. There are 5 wires coming out of the wall by the TV. 1 coaxial cable, 2 Cat5 enhanced wires, 2 ethernet. The 2 cat5 enhanced cords are cut at the end.
My understanding is the set up would be to have the receiver in one room with the speakers connecting to it, and then have the TV in another room, however with the connections I mentioned above, i don't know how to connect the receiver to the TV.
The TV is an older Sony Bravia. Receiver is a Sony STRDN1070.
Does anyone know how to set this up?

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