We just bought an oled lg tv. Love it, but can't hook up surroud sound to it. It has different attachments on the back from our old tv. Is there a different cable I need to purchase?

You might want to call Huppin's and ask, this is a Google forum.

Why are you running the sound out of your TV to the receiver instead of through the receiver first ? Or are you just using a sound bar?

HDMI cords, maybe optical cord

Can't say about your tv, but i have an LCD tv, and all i needed to foo was hook the HDMI cable from tv on three receiver to one of the HDMI ports on the tv and i was up and running.