That'll be the inverter board. It might be the 6632L-0490A made by LG Philips. If it is, you'll find the 2 capacitors have leaked and a bit has blown out of the chip. The inverter board is hidden behind the main board on the 505 model.
Check and replace damaged component/s at its back-light inverter stage circuit, or replace the back-light inverter board. If you wish to get some details; check the site linked here. Viewing it in "Mosaic" will make surf easy. Surf the site with patience.
http://electronicshelponline.blogspot.com/ Pull up older posts there.
You have to specify whether it is an IC, capacitor, transistor, diode etc. and mention its value. If it is an IC, it has unique number written on it, most probably it will be alpha numeric.
Connect TV to a different input device. If it works it is a problem with the set top box or cable. Look for any loose contacts in the RC Cable or RF Cable. Show a torch light on the screen when the program is on and if you can see the picture, the backlight is not getting on. This may need attention by a qualified service technician.
Depends where you look. Comet have a list of appointed suppliers for electronic components. If those suppliers don't have / cant get a particular component, as far as they're concerned, it's no longer available. This doesn't mean it's unobtainable, but Comet aren't going to start searching the internet or asking non-appointed suppliers for it.
It took me less than 2 minutes to locate 2 for you from UK suppliers, 1 new, 1 used. I could probably find some more, if I looked a bit harder.
This is a known issue with this TV. The following might resolve it:
Check Mute and Volume:
Ensure that the TV is not muted and that the volume is set appropriately. Sometimes accidental button presses can lead to muted sound or low volume.
Inspect External Speakers:
If you're using external speakers, verify their connections. Loose cables or faulty speakers can cause sound issues.
Test Different Inputs:
Connect a non-HDMI device (such as a DVD player) to the TV. Observe if the sound distortion occurs. If it doesn't, the problem might be related to the HDMI signal from your Virgin box.
HDMI Troubleshooting:
If the issue persists with the DVD player over HDMI, consider the following:
HDMI Cable: Check the HDMI cable for damage or loose connections.
Virgin Signal: Contact Virgin to inspect the signal/lines and replace the box if necessary.
Mainboard Replacement (if needed):
If the sound distortion persists, it could be due to a faulty sound processor chip on the TV's mainboard. In this case, consider replacing the mainboard.
TOSHIBA 42RV500E, 42RV500T, 42RV500Y, 46RV500E, 46RV500T User Guide (manualmachine.com)
There may be loose contact or track open in main board.So try to check the main board thoroughly where you may find the loose of connection or track open.
Locate the Battery Cover: Look for the battery cover on the back of the remote control. It is usually a small compartment that can be easily opened.
Remove the Battery Cover: Depending on the design, there may be a latch, screw, or sliding mechanism to secure the battery cover. Use your fingers or a small screwdriver to open the compartment.
Remove Old Batteries: Take out the old batteries from the battery compartment. Pay attention to the orientation of the batteries, so you know how to insert the new ones correctly.
Check Battery Polarity: Take note of the positive (+) and negative (-) signs inside the battery compartment. Make sure to insert the new batteries with the correct polarity to match these markings.
Insert New Batteries: Place the new batteries into the battery compartment, ensuring they are properly aligned with the correct polarity. Press them down gently to make sure they are secure.
Replace Battery Cover: After inserting the new batteries, close the battery compartment cover securely. If it has a latch or screw, make sure it is fastened properly.
Test the Remote: Point the remote at the device it controls (such as a Toshiba TV) and test whether it responds to your commands. If the remote is working correctly, you have successfully replaced the batteries.
Dispose of Old Batteries: If the old batteries are no longer usable, make sure to dispose of them properly. Many communities have designated recycling locations for batteries.
Serial numbers don't work Judy
https://www.google.com/search?q=A10A13799C3300
They are purely a numerical identifier of when it was made, year, day, number on the shift, whether it Joe or Billy who did final inspection.
With a MODEL number I can find them easily with just 'make model manual'.
Toshiba
http://www.toshiba.com > support > content
PDF
Thank you for purchasing this Toshiba LCD TV. This manual will help you use the many exciting features of your new LCD TV. Before operating your LCD TV, please.
62 pages
Toshiba
http://www.toshiba.com > support > content
PDF
Thank you for purchasing this Toshiba LCD TV. This manual will help you use the many exciting features of your new LCD TV. Before operating your LCD TV, please ...
62 pages
..