I have a 4k LG curved TV model no 55c6v & have connected the optical output to my Harman amp optical output ....I just cannot get a sound out of my headphones without sound issues ...Noise , buzzing increasing volume etc ...It can work fine for hrs then next day problems again ..the TV set up that I have selected is LG audio out ( optical / HDMI ARC ) & Dolby digital ...Amp setting ...using optical 2 ...& digital Select optical source 2 & source VID2 ..it says PCM on front of amp ...Were am I going wrong ? I am sick & tired of trying to get this right and would very much appreciate some help ....Using standard JVC headphones