i have tried two different kinds of splitters and neither of them work. here is what i'm trying to do. hdmi cable split off my cable box. one side going to the tv and one side going to my denon reciever. the reason is so the i have watch tv with out turning on the surround sound and just use the tv volume. theses are the two that i tried.

HDMI SPLITTER CABLE ADAPTER FOR PC HDTV 1080P 2 PORT | eBay

and

HDMI amplifier splitter 1x2+ HDMI 3ft Cable 1080p | eBay