Why does my sound only come on sometimes when i get to the log in screen for World of Warcraft?

Question

Product: HP Pavilion dv9628nr
Operating system: Vista
Error Message: (i dont know if it is an error message) "No Audio Output Device Installed"
All I did was play the latest content for World of Warcraft (Patch 4.3). I hit the mute button and it turned red. I hit "exit" and "exit now" after i was done playing and it took a long time to exit. After it was back to the very familiar screen with all the icons the sound was gone. The mute button was blue after a restart, then it started saying i didn't have a sound card when i tried looking for it. The next day i turn on my laptop and and the mute button is red when it's starting up. After it was done I unmute it and sound worked fine, but for a while. After that the sound only comes back on a few rare occasions when i get to the login screen of world of warcraft. Then after a while of walking around doing nothing, the sound is gone again, but the mixer is still there (the mixer disappears after i restart). It also doesn't let me successfully uninstall the sound driver. I restart and go to reinstall the driver on the website, but during the download it says that it's already installed and if i want to overwrite, when i hit "yes to all" the lap top beeps LOUDLY, and says the installation failed because it didn't find the device. What's going on?

Answer 1

The boot ROM is static unless Apple issues a firmware update. I just checked and they never released any such updates for the eMac. Without a firmware update available, I know of no way to overwrite the current version.
What did the serial number check show? Don;t post your serial number, just whether it fell within one of those ranges.
The logic board issue was specifically bad capacitors. Look at some of the pic posted here:
http://picasaweb.google.com/gdegagne/EMacCapacitorReplacement#
Open your RAM door on the case bottom and look inside. The third picture in the web site is the view with that door open. You can see only two of several possible bad caps through the RAM door but, if those two are leaking brown goo like those in the image, I think you will have found your problem.
I just realized you are in Tacoma. That makes the closing of the repair place I mentioned all the more sad, as your shipping costs to Eugene OR would be much less than for an eMac owner living several states away. Heck, you could have driven it to Eugene!
Really, I'm not in the habit of preaching 'gloom and doom' but, in your case, we need to deal with the logic board issue first to be able to provide you with worthwhile help should your computer not have the "bad cap" problem. If bad caps are the problem, there is not much we can offer other than to refer you to Google to search for self-repair instructions, or to Apple Customer Relations (1-800-767-2775) to consult regarding a Repair Extension Program that was apparently shut off too early.