Gettin audio I have attached a laptop to the protron lcd tv. I can get the picture but no audio. I have connected the audio plug, everywhere on the tv that siads audio in...with no luck...Help! Maria

There are several performance issues you may encounter with your Protron PLTV-37C LCD television.
Some problems include the television not turning on, issues with the TV's picture and issues with the TV's sound.
Depending on the type of problem you encounter, there are several options available to you to solve it.
Power Issues
Check the TV's main power cord. If it is not plugged in or is loose, securely plug it in to an electrical socket.
Unplug the television and plug it in to another electrical socket.
If the one it is plugged in to currently is bad, the television does not receive power.

Try turning the television on with the remote.
If that does not work, try turning the television on with the power button on the TV's front panel.
If that works, then remove the battery cover from the remote.
Remove the current batteries and replace them with fresh batteries.
Picture Issues
Check the video cables.
If they are loose or disconnected, securely connect them.
Adjust the television's brightness.
If the brightness is set too dark, images on the screen are extremely difficult to see.
Check the power indicator on the front panel of the television.
If it is red, the television is in power-saving mode.
Simply press any button on the remote to bring the television out of power-saving mode.
Audio Issues
Check the audio cables. If they are loose or disconnected, securely reconnect them.
Turn to different channels and adjust the volume.
It is possible that some channels are coming in quieter than others.
Access the audio options from the main menu. Check what audio setting the TV is at.
If it is set to "Mono," change it to "Stereo."
http://www.retrevo.com/search/v2/jsp/downloadPage.jsp?doc=dde1880d298054849d8c8adc90514f40&modelid=22971545&q=Proton+CS-37
Specifications for Proton CS-37 / PS-47

Try replacing the main board

The tv have a long board call the LCD inverter board.This long LCD inverter board is dead.This long LCD inverter board job is to help the LCD screen panel to have a backlight to produced a picture.Tries websites like Shopjimmy.com,Ebay.com to buy a long LCD inverter board for the replacement.

Hi.

If there is sound but no picture, screen is completely dark and the picture is occasionally flashing, then the fault is likely a faulty inverter. In some case a faulty controller board or a defective PSU can cause the same problem.

I summarized the problem here:My LCD TV has sound but no picture.

I posted general procedure to test inverter, PSU and controller board on LCD here : How to test an LCD TV or monitor PSU and inverter.

If screen is not dark, but has blacklight or noise things are different. In that case check connection cables first. Parts that may be defective are main controller board, terminal circuit and tuner board.

Protron parts are available using the link below. Ensure that parts are compatible with your model before purchasing.

ShopJimmy - Protron Parts.

Regards.

It can either be the backlight inverter board or the power supply is not supply 24vdc to the inverter board.

I had also a problem like that before while watching movie brain works for free,earn adds by Google and sponsored by the queries.The usual problem are the two speakers attached to the pannel since they are thin and small they cannot handle the audio range of the sound output of DVD movies.They are usually busted, other rare case is the earphone jack,it disconnect the speakers when phone is plugged in, the connection must restore after earphone is unplugged.Please vote for links... thanks

If you need to connect to DTV,you must have RCA cable(video/audio cable,could be component video cable and audio left and right!) Also,in order to have that connect it,you need to have a cable box,directv or dishnetwork box that got the component video output. If you are connecting the coaxial to the TV,you are not going to have any signal in the DTV connection,cause there is anything connect it to there!
solutiondoct

Easy! If you have a VCR,put a VHS tape in the VCR,run the video cable behind the TV and the audio cable from the VCR to a hi fi receiver/speaker(cd input or tape input.)
If you have sound coming out from the HI FI,go ahead and plug the audio connection along with the video connection behind the tv.If there is no sound, it could be:
A. your TV speaker is completed its mission-;o)Blown speaker.
B. you are on TV MUTE!
C. your audio cable is defective(small chance,cause you have left and right!)
D. your connection was incorrect.
solutiondoct

Go to the set up menu and select audio. check that the speakers are ON.. Then make sure that stereo is selected. If the set is set to alt sound there wont be any sound.

i had the same issue with a thinkpad T61 which i was connecting using VGA and a audio jack going straqight from the headphone socket to the back of tv.
I had picture but no sound and i found that once connected the issue could be solved by rotating the projection setting on the laptop(Fn+F7). Basically switched back to laptop only display, then back to laptop and projector display again and teh sound just kicked in. 
i think it's related to the projector setting on the laptop rather than an issue with the tv.