Arc won't work

[Inoverhishead]

Just brought a lg nb4540 sound bar and sub, and have a lg 32lb580v TV, when I connect the sound bar through the Hdmi arc I don't get sound from any of my devices, i have a virgin cable box and pc connected to the TV
Can anyone help

 

[martinch]

I take it you've connected the HDMI ARC lead to the HDMI port on the TV marked "ARC" and one marked "ARC" on the sound bar? And you've told the TV to use external speakers (rather than the built-in ones), if there's an option to do this?

 

[Inoverhishead]

Yeah I changed the settings on the TV to
External speaker(Hdmi arc) and the connection on the soundbar is Hdmi out, which is what the manual suggests but for some reason it still doesn't respond