Onkyo TX DS797 no sound from cable TV

Make sure your X Box is switched to component and not hdmi.

How To Connect a DVD Recorder to a Television:
1.If you want to use higher quality cables, then you may want to connect the TV Source (Cable and Satellite only, not Antenna) to the DVD Recorder using Composite, S-Video or Component video and audio cables.
2.To use composite cables (also known as RCA, the yellow plug is video, the red and white plugs, audio): Plug in the composite cables to the RCA outputs on the back of your TV source and then plug in the composite cables to the RCA inputs of the DVD Recorder. Then connect the RCA outputs from the DVD Recorder to RCA inputs on the TV.
3.To use S-Video and RCA audio cables: Plug in the S-Video cable to the S-Video output of the TV source. Plug in the S-Video cable to the S-Video input on the DVD Recorder. Next, connect the RCA audio cable to the output on the TV source and the input on the DVD Recorder. Finally, connect the S-Video cable and the RCA audio cable to the output on the DVD Recorder and the input on the TV.
5. To use Component Video cables and RCA audio cables: Connect the Component Video cable and the red and white RCA audio cables to the outputs on the TV source and the inputs on the DVD Recorder. Next, connect the Component Video cable and RCA audio cable to the outputs on the DVD Recorder and the inputs on the TV.
6. Now that the TV source (either Cable, Satellite or Antenna), the DVD Recorder and the TV are all connected, you need to configure everything to make sure that TV is coming through the DVD Recorder, for recording and viewing.
7. Turn on the Cable Box or Satellite Receiver, TV and DVD Recorder.
8. If you connected everything using the RF connections then the TV should be passing through the DVD Recorder and displaying Television on the TV screen. To record in this mode, you would need to tune to either channel 3 or 4 on the TV and then use the DVD Recorder TV Tuner to change channels and record.
9. If you made connections using either Composite, S-Video or Component cables, then to view or record TV, two adjustments need to be made. First, the DVD Recorder needs to be tuned to the appropriate input, typically L1 or L3 for rear inputs and L2 for front inputs. Second, the TV also must be tuned to the proper input, on a TV usually Video 1 or Video 2.
10. If you have a Dolby Digital 5.1 Surround Sound A/V Receiver you can connect either a Digital Optical Audio cable or Coaxial Digital Audio cable from the DVD Recorder to the receiver to listen to audio through the receiver.

Have you seen the user guide?

http://ec1.images-amazon.com/media/i3d/01/A/man-migrate/MANUAL000036122.pdf

The TV is intended to be an end point of the video, not a source of audio. Many TV's (monitors) don't have ANY audio, much less surround sound capability. Composite Video is theminimalist video connection for setup; Component video to the TV should suffice for viewing DVD's.

Is your TV the SOURCE of surround sound programming (via an antenna) or does the programming come from elsewhere like a Cable Box? THAT would be the source you need to tap for surround sound.

If you have the AV cable that has the switch on the Xbox end, make sure that it's in the correct setting. Your cable could have shorted out if this does not work.

It would be helpful to know what type of TV you have what type of cables and what the source is. (DVD, SAT or Cable box)If you are using HDMI then it could be a resolution issue. the source resolution cannot exceed the range of the TV. the current standard is 1080p, there are some older TVs that can only work up to 720p or some that will work to 528p which is an EDTV standard.
another reason could be if you are using component video cables. there are three video cables that make up a component video HD system. the Green is the sync and if it is unplugged you get no picture. the other two (blue and Red) will only give you an odd tint to the picture. check the green component cable and even switch it at both ends with the blue or red cable to check if the cable itself is bad.

Are you using AV or component cables?

*Solution for AV Cable*
Check to make sure the cable is fully plugged into the port. Having it even just slightly out of the socket will render no video. If this doesn't work, try plugging it into a different port on your television to make sure the port isn't bad. If you still have no video - the video part of the cable could be bad and you might need a new cable.

Also make sure that if your cable has BOTH component and AV connections available that the switch at the end of the cable near the Xbox is set to "TV" as opposed to "HDTV"

*Solution for Component Cable*
Also check to make sure that all the video connections are fully plugged in. If even one of them isn't plugged in fully, it could render no video. Also make sure that you have them properly plugged in to the right color. If you're just quickly connecting it to the back of the TV without proper lighting, it can be easy to confuse the blue and green connections.

When using component, make sure that the switch at the end of the cable near the Xbox is set to "HDTV" as opposed to "TV".

The cable your refering too are called Component leads.

The red and white are for your audio and the remainder are the video. All you need to do is connect the component leads matching up all the colour in the correct ports then using your av/source button change the tv to component
You will still have to connect the red and white audio cable to the tv as well.

that should sort your xbox out.

cheers

Little Dish Fitter

check the system settings of your console and make sure everything matches what your tv supports. Also check the tv settings so that it reveives audio from the HDMI cable

Sounds like a power board problem.Does the tv return to stand by?Red led

If your TV is HD, you should definitely be connecting the component video cables (green, blue and red) from the 360 to the TV (the 321 will not do video pass-thru from component cables). -Make sure you have a picture at this point. (TV switched to whichever input you connect the 360 to)
You can get an RCA extension cable for the audio portion (red and white) to connect to the 321 for audio. You could also connect an optical audio cable to the 321. An optical cable must be assigned from the system menu to work..
Let me know if this helps.