Can't get surround system to work with tv programs

[Ruffyy]

Hi please help. I have an LG 55UH605V and a sony BDV-N7200W 3D/bluray Home theater system.

The HT (home theater) is connected to the TV via it's output HDMI (ARC) and into the HDMI (ARC) in the tv.
When I I put on the tv there is no sound at all from the speakers. I tried changing the ports into non arc ones and still no sound. What am I doing wrong? Do I need an optical cable is that the only option?
Yes I've tried to change output sound from tv to hdmi arc and not internal tv speakers.

However when I connect my laptop to the HT then I can transfer audio and video to my tv with sound to the speakers. When I play movies I feel like I'm not getting the surround sound (even though weak sounds do transmit in rear speakers), but if I play via USB for example I feel like the sound is surround. Why is this?
I'd appreciate any help, thanks.

 

[jsmithepa]

Not sure. But Toslink should work.

 

[americanaudiophile]

You have to have ARC in both the TV and HTS and I don't find mention of it in the Sony HTS manual. You will have to use an optical cable. You often have to turn this on and the TV speakers off in the TV menu. Set the TV to output in surround sound too.
On most surround sound systems each input remembers the last surround sound mode it was set to. For disc playback the Sony will set itself based on the disc and which audio you select on the disc menu.
For TV and cable you would leave the HTS on Dolby, This will give you Dolby Digital surround on the channels that have it and Dolby Prologic surround sound on those that don't.
Most movies make limited use of the surround channels. Make sure you have the channels balanced as per the manual. This will give you the correct levels out of the speakers that the sound engineer wanted. Non digital surround sound like Prologic synthesis surround sound by finding out of phase sounds on a stereo signal and sending them to the rear so you often get unintended rear sound when not in digital surround. Try the different surround modes and use the ones you prefer.