Panasonic smart tv tx 50 as 540b,,has no guidance to set up arc ,,has optical connection ,,my Samsung home centre has no optical connection ,I use rca adapter ,my DVD surround sound is fine ,,unable to get surround sound from my TV, surround setting goes back to stereo every time I try set ,viewable link is not helpful either
Trying blindly is not going to get you nowhere, today's audio more complicated than ever.
Warning #1. "HT Systems" aren't very flexible, oftentimes they do 1 thing and that's it, not designed for you to hookup multiple sources to it and expect it to cooperate, unlike an honest-to-God AVR (Audio Video Receiver) with stand-alone speakers.
So no Optical, that's bad news. Your next option is HMDI ARC, both pieces must have this and enabled, consult manuals for their existence if u have to.
Last option is an Optical to RCA converter, if your HT system as LINE-IN/AUX-IN, if available this gives you stereo only, no surround.