Audio Issues - Sound stops on youtube vid after a few seconds. Please Help?

Question

What's been happening is weird audio issues, especially youtube  related though not only (other web video content has been messed up, but  mostly youtube). Right now I am using headphones (1/8" or 3.5mm)  through the back of the computer and when I turn on  the computer, at first I can hear sound from videos. When I open the  speaker icon mixer window in the bottom right, I see green bar moving  with the sound on the "speakers" mixer and "Adobe Flash Player" mixer  simultaneously.
Then after a few minutes or after having a few tabs open, all of a  sudden the audio stops. Oddly enough, usually the video keeps going even  thought the audio has stopped. I verified this wasn't a hardware issue  with my headphones by opening the Speaker Icon  Mixer window, and acutally was watching it at the moment the sound  stopped and saw the green bar disappear exactly when the sound stopped.
If I restart the computer, or firefox only sometimes (mostly need to  restart cpu though) then videos will play again with sound. Once the  sound stops however, if I open a new youtube video in another window, it  will sometimes cause an "An error occured.  Please try again later" crash.
I'm at a loss of what to do.
Running latest version of Firefox (26.0) and Adobe Flash (11,9,900,170  installed). Windows 7 64 bit system, Intel Core I7 Processor.
I have tried many things include "reset firefox", clear cache,  changing to an earlier version of Flash (11.3). Tried to update sound  cards. Even tried to restore computer to an earlier setting ( I only  went two days ago, could go farther back I suppose).When  I reverted back, the problem went away for a few hours but then came  right back.
I scanned pc with ESET online antivirus, no viruses, Malewarebytes  Pro, no issues. Cleaned with CC cleaner. Plenty of hard drive space  (using an SSD boot drive btw).
I am not very knowledable about plugins or "addons" or extenstions.  Nor do I know if it has anything do "Firefox Options -> applications"  (gives content type and then option...essentially a bunch of sound file  types and then which plugin plays it). I can  give my list of all this out if necessary but there are quite a few and  I dont know how to copy/paste that info so it would take. Even though  its gonna take forever to hand type these guys all out, I will give my  list of "plugins" that may be audio related:
QuickTime Plugin 7.7.4 7.7.4.0
RealDownloader Plugin 1.3.3.66
RealNetworks (tm)
RealDownloader Chrome Background Extensions Plug-in (32-bit) 1.3.3.66
RealNetworks (tm)
RealDownloader HTML5VideoShim Plug-in (32-bit)
1.3.3.66 RealNetworks (tm)
RealDownloader PepperFlashVideoShim Plug-in (32-bit) 1.3.3.66
RealPlayer Download Plugin 16.0.3.51
RealPlayer(tm) G2 LiveConnect-Enabled Plug-In (32-Bit) 16.0.3.51
Shockwave Flash 11.9.900.170
Shockwave for Director 12.0.7.148 (for netscape plug-in)
Shockwave for Director 12.0.2.122 (for netscape plug-in)
Silverlight Plug-In 5.1.20913.0
VLC Web Plugin 2.1.0.0
When I open my device manager and look at "Sound video and game controllers" I see 4 options:
1)AMD High Definition Audio Device
2) Bluetooth Audio Device
3) High Definition Audio Device
4) Intel (R) Display Audio
I'm not sure what this means, if I have 4 sound cards or if they are conflicting somehow.
I tried to update drivers on each one. No change.  I've tried  "restarting firefox with addons disabled" and "check here to see if your  addons are up to date" (they were except VLC which I did update before  restoring to previous day and it didnt help).
None of the fixes work for me, same issues. Extremely frustrated!! Help?

Answer 1

I'm having a similar problem with flash audio. After a few minutes of watching a video or playing a game the audio cuts out but the video keeps working. The audio does not return until I refresh the page. The issue occurs regardless of which browser I'm using (have tired both Firefox and Chrome). Oddly enough, when the audio cuts out from whatever flash application is running, my entire system loses sound until I refresh the webpage or close the browser. For example, I was playing Minecraft with Chrome open in the background and suddenly the sound cut out from both. Once I closed the browser my audio came back. I realized that there was a graphic on the webpage that was flash based which likely triggered the issue.
I do not have any Real plugins.
Incidently I also have Intel (R) Display Audio listed in my device manager
Edit: I forgot to mention, this issue only seems to occure when I watch videos that have been uploaded recently. For some reason the audio does not cut out when I watch a video was uploaded a few months ago.