Intermittent loss of audio single

Hi Geoff, I hope I can help you with this. If you are using an accessory device (DVD, DVR) check cables to see that they are secure and if device has audio out option that it is set correctly. Also check to see that Video and Audio cables are connected to matching inputs on your set.
If you are using DVI to HDMI you will need to use a separate digital audio cable. DVI cables do not carry audio signal. After attaching the audio cable if you still do not hear sound you may need to set Digital Audio In. To do so:

1. Press Menu Button on remote.
2. Press the cursor ring down to highlight SETUP.
3. Press the cursor ring left to enter SETUP menu.
4. Press the cursor ring down to highlight SOURCE.
5. Press the cursor ring left to enter SOURCE menu.
6. Press the cursor ring down to highlight DIGITAL AUDIO IN.
7. Press the cursor ring down to select the source you want to associate Digital Audio with. HDMI 1 or HDMI 2 in this case. You might need a software update also.
   The latest software solves the issues below:
   
   1. TV (Plasma 42" and 50") will not turn ON/shut off itself and Red LED blinks 4- times. Recover if main switch on/off.
   2. 37" LCD full white screen appear when upgrade software.
   3. Some channels not available after turn ON.
   4. Delta volume changes, not remembered.
   5. Preferred channel changes, not remembered.
   6. Green or yellow static (sometime snowy) on HDMI picture.
   7. Picture and sound loss for 5 to 10 sec (green LED is still ON) and back to normal.
   8. Audio loss in all inputs and can be recovered when main switch ON and OFF.
   9. TV set turn ON by itself/ green LED light up and goes off when set is ON.
   10. Intermittent audio loss in NTSC RF channel.
   11. Crack sound with high input signal.
   12. Include the possibility to download the rating table (RRT5 capability) for digital programs.
   13. No video/ no picture with sound.
   14. Intermittent On-Screen Menu pop up by itself and can be removed by pressing the 'MENU' button.
   15. Channel information display too long.
   16. Improvement on scramble channel.
   How to check the current software version on my TV set?
   
   1. Press 'MENU' button on remote control to display the on-screen menu.
   2. Select TV MENU and press the cursor right.
   3. Select INSTALLATION and press the cursor right.
   4. Select SOFTWARE UPGRADE and press cursor right.
   5. Select CURRENT SOFTWARE INFO to display the current software version on your TV set.
   6. If the TV software version is lower than the version posted on the website means your TV set needs to be upgraded.
   7. Follow the instruction in the user manual or Firmware Upgrade Readme file on how to upgrade your software.
   Where can I find the latest software for my TV set?
   The Firmware Upgrade Software and Readme File documents can be found on the Philips support website. Refer to the SOFTWARE section.
   

Fault with the main power supply regulator board. Check and replace damaged component/s at its main power regulator [SMPS] section circuit. Contact any service technician. If you wish to get some details; check the site linked here. 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 rather than making "Surgery" to it; which usually will make loss for both money and time. Even though you can make it right, it will cost around an amount equal to the cost of a new board; including the cost of (spare parts + service charge) More to say, most of the spare parts to it will be difficult to get from open electronic spare part market. This is true to most of the flat panel TV power supply boards; irrespective of its brand and screen size.

I have a Vizio E320VL - just hooked up the HDMI for the first time (4 years later) to work with my new comcast HD DTA. I'm getting "retrieving data" (with really weird audio sounds in the background) - then "not support." If I wait a few minutes, I can change the channel and get clips of video/audio with some intermittent gray snow and black screen - The longer I leave the TV on, the better this gets until its almost running fine 30 mins later.

What brand/model is the receiver. Some have a function where you can select if the audio is passed through to the tv, or output from the receiver's speaker jacks.

did you check this out yet? (from the owners manual)

IMPORTANT NOTE: If the AVR's video output resolution

is set higher than the capabilities of the actual connection,

you will not see a picture. If the best available video connection

from the AVR to the TV is composite video, press this button
and change the resolution to 480i.

Settings are not the source of intermittent problems.

"Signal loss" is indicated WHERE? So what's going on upstream at the source? ITS cables are a part of this.

My $.02... I never route any signal unnecessarily to or through a device that doesn't enhance or consume it. Hence, my BEST video from each of my several video sources goes directly to my TV/monitor and my BEST digital audio from all sources goes directly to my AVR.

No problems.

You need to make sure that the settings on your TV for the DVI connection are set properly. It sounds as if it is set to stretch or zoom. The reason the HD channels look great is that they dont zoom because the resolution fills up the entire screen without stretching.

I know you want to use your HDMI cables, but since you are going HDMI to DVI you are removing the benefit of the single cable since you still have to use audio cables. You are not going to get any appreciable difference between the setup yo uare using and the component (red, green, blue) cable.

If I have helped you, please rate me as such. It allows me to help others. Thank you.

have you tried to change the audio settings to HDMI on tv? when u have HDMI hookd up u have to change the audio to HDMI also

I had the exact same problem on a brand new Insignia 26 " LCD with DVD. Comcast tech was able to fix it by changing the Comcast box diagnostics. Here is what he did. Using the Comcast remote with the TV on - press power, cable, menu in that order. A comcast diagnostic srceen will appear. Select Additional HDMI options, then audio options. Change the audio options to L-PCM. Press power again to exit the diagnostics. That will fix it and you get to use the HDMI cable.

a switch box is needed the s video shares the red/white audio with the yellow rca that is being used already