I'm looking for troubleshooting advice on connecting an LG Smart TV to a Vizio Soundbar with an optical cable. I changed the setting on the LG TV (photo attached) and tried various ideas for getting sound out. It is not muted and the soundbar works fine with bluetooth. I can see a red light at the end of the cable on both ends whatever that means. I believe the hardware connection is correct. The tv is model 50LF6090. Any additional troubleshooting advice would be appreciated. Is there a method to test the optical output port on the tv? Thanks.