I've never had to use any optical cables on my tv before or with my other older Roku players. I have an older Sony Plasma tv. No ARC port for the HDMI cable, so I also have to attach the optical cable provided to the optical port. I'm clear on that. The only thing is, the ends of the cord don't seem to want to connect to either the port on the Roku Streambar or on my tv. Is there some special way it needs to go in to make it connect properly. This should be simp!e, right? On the one tutorial I saw online, the cord they used looked thicker. Do I have to buy an optical cord?