The only issue I've had with ARC (LG TV and Denon receiver) was with remote control and those issues are long gone ARC settings issues with the receiver that I just had to work through. My Harmony Elite controls volume and all other functions of all of my devices including my TV, and my LG remote controls both LG apps on the TV and volume on my receiver. Sound from the LG's apps not only works, I'm getting 5.1 sound and Atmos across ARC. If it works with my setup and for tens of thousand of others then it's either a defective or incompatible device (TV, receiver, or the cable itself) or a settings issue. Anyway I'm out of ideas so I'll let you guys figure it out. Best of luck.