It depends on which particular HTIB you are referring to
. They all have somewhat different inputs/features/etc. Hypothetically though, it's a combination of HDMI, digital optical/digital coaxial cables/connections for both video & audio depending on which components are involved. If you list the exact make/models (cable box/HDTV too), I can suggest a 'recipe' to connect the whole shebang
.
best,
Pedro
Hi. I am looking into buying a HTIB system but had some questions first. I need to hook up a cable box, xbox 360, and a HDTV to the HTIB but I want to make sure I will be able to get high quality audio through my HTIB for each of these. I am trying to figure out how I would connect all these elements.
Any advice would be greatly appreciated. Thanks.

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