My problem: I have an HD TV with the HDMI cable and all that good stuff, but I want to record my gameplay with my SD capture card while playing in HD. Is it wise of me to pop off the blocky thing on the Xbox A/V cable (and cover it with electrical tape or something) in order to plug in both the HDMI cable and the A/V cable? It seems I can also only use my Turtle Beach X1's with the A/V stuff so I'd need to plug them both in to use my headset with HD. Anyway, I'm not sure if plugging them both in will cause any serious problems for the Xbox or anything. Halp?
You'll need some kind of converter or an HD capture card. There's no way without getting more equipment.