We might be able to help if we could understand your problem. "Cannot get the sound working for each component the way it used to" is not a problem which we can solve. Could you describe how you had it connected before and the TV you were using. Then tell us how you have it connected now and why that is not satisfactory. The description should include what output is connected to what input including the connection type such as composite, component, HDMI, analog left/right audio, digital audio optical or coax, and coax RF for example.
If it isn't 720p or 1080i/p it isn't HD. If it is 720p or 1080i/p it may not be HD content.