If you only have cable with no cable box (with a splitter on your cable at home) then change channels on your slingbox to your heart's content and the picture at home won't be altered. It's when you have a digital cable box when the picture changes at home along with what you are watching on your Slingbox. I have my DVD player hooked up as well and as long as somebody puts in a DVD for me I can watch it via the Slingbox. Stuck in Japan for 6 months and the Slingbox is a savior!