I have a VIP 622 connected to a Sony 60" tv with HDMI. The Sony tv is connected to a Sony surround sound system with what appears to be rca jacks. The tv sound is turned off, I always use the surround sound system. Questions: 1. Would optical cables provider better sound? 2. Should the optical cable connect the sound system to the tv or the 622? 3. Would I really notice the difference?