Problem With Xbox 360

Okay so, I tried playing my Xbox 360 today but for these past few months I've been having difficult doing that. The main problem is that I cannot see the display for the Xbox dashboard nor can I view the visuals for any of the games. I either get a black screen or a "no signal" message. However, I can hear what's going on. Like for instance, if I'm shuffling through the dashboard I can hear the sound it makes when I shuffle and I can also hear video game music. Stuff like that, yet I cannot see what the heck is going on. The television I'm using is a Sanyo HDTV DP19647.

I'm certain that all the connection cables are in right because I can view television shows and movies via Comcast Digital cable box without a problem. The input for that stuff is input 3 or simply changing it to channel 3. The input for when I want to play video games on my Xbox 360 is input 2, but I cannot get a signal at all. I tried changing it to other inputs to see if that would work, but it hasn't. I'm not sure what's going on here, but I've been having this problem on and off for at least five months now. I usually got it to work before after turning the television off and rebooting the Xbox 360, but neither of those things seem to be of any use now. I'm at a lost. What should I do aside from calling technical support?

If it's still on warranty then you could call tech and they will give you a new one. :)

It's most likely the cable connecting the Xbox to the TV. If you have a friend with a 360 you could try their cable and if it works you've found the problem.

If it doesn't work then it's either the TV or the Xbox. To rule out the TV, try connecting your Comcast box to input 2 (assuming input 2 has the same sockets as input 3). If that works then it's your Xbox, so send it away for repair. If not it's probably the TV, in which case you could connect your Xbox to input 1 or 3 and you'd be able to play.

You should also rule out the facepalm things like checking your 360 cable is plugged into the TV in the right order, i.e. making sure the video plug isn't in one of the audio sockets, etc. If you're using standard A/V (red, white, yellow plugs) then red and white are audio; yellow is video.