Sorry, I should have been more clear. I'm aware of what the audio outputs on the TV are; I'd be using the RCA output from the TV to the 1/8" headphone input on the speakers using a short converter cable. The Audioengine speakers only accept 1/8" headphone.
I'm wondering if once I set it up this way, if I'll be able to control the volume of the output from the speakers by adjusting the TV volume. On my current TV, using the connection described above, I have to adjust the volume on the speakers. The TV volume adjustment has no effect.
I think some TVs have variable audio output while others are fixed, or have a setting to turn it on/off. Wondering if this Vizio has it.