Sony TV is now so quiet!

Check and replace damaged component/s at it main power regulator [SMPS] section circuit. Contact any service technician. If you wish to get some details; check the site linked here. Viewing it in "Mosaic" or "Magazine" will make surf easy. Surf the site with patience. Pull up older posts.
http://electronicshelponline.blogspot.com/
It will be best to replace the power supply regulator board as card basis.

First if HD via component or HDMI the hookup or more likely the box if used is your issue---some sets will require a firmware update for certain boxes to work--I am guessing but guess you may be using HDMI.

I'm pretty sure that the buzzing sound is a not normal thing for an LCD TV. I sell Flat Panels during my spare time and it should be as quiet as a CRT types. It is more likely a defect and you should return it ASAP.
Hope this helps.

Power supply problems. check SMPs and other feed back voltage signals.

sounds like a bad reley to me time to open up the patient and find the little bastard

A service technician arrived at my home this morning and infromed me that 13 blinks indicates a bad LCD panel. His quote to repair it was approximately $500 more than the TV initially cost. I contacted Sony support directly, and they have agreed to replace the TV, since it is less than 30 days out of warranty. The KDL40V3000 has apparently been dicontinued so they are replacing with a KDL40V4100(factory reconditioned). I know this won't necessarily help others with the same problem, but if your warranty ended recently enough they will probably work with you to mitigate the expense.

While you have sound, take a flashlight and shine it on the screen, look very close and see if you can see a dark video image.
Let me know what you see.
lone99star

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/jason_77a19afa8d604dee

Check your surround or expanded sound settings, make sure they are all off.

Component 1 on the TV is probably an input, not an audio output. You need to find out if your TV has audio output jacks.
If I'm mistaken, and you are using audio output jacks from the TV, then you just need to press FUNCTION on your remote until the LCD display says "TV/VCR".

I had the same exact problem.
I removed the bulb and cleaned it. There is a small screen at the top of the bulb and it was covered with dust. Once it was cleaned I replaced the bulb and it solved the problem.
Thanks to those who posted the solutions