Set TV to Auto ON/Auto Off.

Check its picture settings first. If color intensity is decreased to Zero, there will be no color to picture. Get into its picture set up option, and check this first. If it is found normal, check the system settings, such as PAL, SECAM, NTSC etc. If there is an option to select the system settings to "Auto" (if your TV is a multisystem one, this option will be there), select this option"Auto".
If nothing of above said help you, contact any service technician. Gopakumar Gopalan Google

Hello
If you are connected your tv with a set top box, check the set top boxes' connection,and its settings according with it user manual. If the system set has varied to an other, this type of trouble will occur. If your are cabled, check the system adjustment of your Tv, and it is best to make it auto. Go through its manual and refer to the sound adjustments, and set the system to auto' If you have this option on remote control, "system Button", press it repeatedely to get the system set to auto. OK.

You need to go to TV on screen HDMI sound set up, you can choose AUTO or select the sound to be through HDMI or through the audio ports, check your laptop HDMI sound set up also. I would set them to 'AUTO'

Follow this steps and try

in windows 7
On the start screen, scroll to Tasks, click settings, click TV, and then click Set Up TV Signal.

Follow the steps to connect a TV signal, depending on the type of tuner or tuners that the cable is connected to

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else try

The Windows Media Center TV Pack has an "Auto Select" option which removes channels that have a weak signal from the EPG. To run the "Auto Select" option to check the list of available channels and to evaluate the signal strength for each channel, follow these steps:

1. Start Windows Media Center.
2. In the Start window, scroll to Tasks, click Settings, and then click TV.
3. Click Guide.
4. Click Edit Channels.
5. Click Auto Select.

The "Auto Select" option tests each channel. Based on whether a strong or a weak signal is found, the "Auto Select" option puts a check mark in the box next to the channel. As soon as the detection process is complete, you have to click the "Save" option to save the newly selected channels to the EPG.
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esle if the problem still persists
have a look aon the microsofts support in the following link

http://support.microsoft.com/kb/955485/en-us

pls check and selact in your tv colour system PAL / NTSC / AUTO
set Auto colour system is Best .
set chennal Auto serch
if not
then problum is in side tv pcb. so repare pcb with nr. thech.

pls check your tv colour system it is not maching with your country col-sys [PAL /NTSC/SCHAM] so pls open menu and set col-sys select any one or set col-sys is AUTO see the colour pictur.
* NO colour [B&W} pictur
[1] cabel singnel is wek.Pls. check cabel canaction re set pin or cabel canaction.
[2] pls tune ch. set Auto serch or fine tune to set ch.
if not colour pictur then problum is inside of your colour tv set.

Have you checked the widescreen setting? Is it set to auto? If it is it wll change if the picture is not 16-9. Most sets have the option to switch it to a number of settings away from auto, including 16-9. So have a default auto setting, which can be set to 16-9.

Setting Up the TV
After you have finished connecting your TV, you can use Auto Program to set up your
channels. During Auto Program, the TV will automatically search for available channels and
program receivable channels.
(Make sure CABLE is connected on coaxial and you are not using any other connections such as cable box, hdtv or satellite antenna)

1 Press to turn on the TV. The Initial Setup screen appears.
2 Press on the remote control or on the TV front panel to start Auto Program, or press
to exit.
To perform Auto Program again
1 Press .
2 Press g to highlight Channel Menu.
3 Press f to highlight Cable. Press to select.
4 Press F or f to highlight On or Off according to how you connected your TV. Press to
select.
5 Press f to highlight Auto Program. Press to search for channels.
6 After Auto Program finishes, press to exit.
To reset the TV to factory settings
1 Turn the TV on.
2 Hold down on the remote control.
3 Press and release the POWER button on the TV front panel. The TV will turn itself off,
then back on.
4 Release .
✍ When you start Auto Program wait until it is finished; otherwise it will skip over channels that are
available. Perform Auto Program again to program receivable channels.
✍ The Initial Setup screen appears each time you turn on the TV until you perform Auto Program.
Initial Setup
Auto Program [CH+]
[CH–]
First please connect
cable/antenna
Exit

no audio / please send me the frequency for ahmedabad city

Check first the antenna using another TV. If there is no other TV available, check using an ohmeter. If you are 100% sure tha the antenna is ok then the antenna connector on your Tv is not making a good connection to the antenna plug.