here is a nice article on how to bypass the problem without paying more money.
http://www.slashgear.com/hack-use-a-cheap-hdmi-cable-on-your-xbox-360-premium-037755/
Microsoft loves money, your money to be exact. When you buy something like their Xbox 360, they want you to use their special proprietary hardware. Take the wireless adapter, you’d think any old adapter would do the trick, unfortunately you have to buy the $100 one from Microsoft. (Or at least that’s what they want you to think, but that’s a story for a different day). Another great example is the $50 HDMI cable with the audio adapter, that’s way too expensive.
If you have one of the newer Xbox 360 Premium consoles, you likely have yourself a nice HDMI port. Unfortunately, due to the design of the A/V cable, you can’t have both an HDMI cable and the A/V cable (which carries your audio) plugged in at the same time. The Microsoft solution is to pay $50 for a special cable.
The hacker solution is to remove the plastic casing around the connector for the A/V cable. This gives you enough room to plug in an el cheap-o HDMI cable. Take that Microsoft!
