No Audio Output is Installed in ASUS X555LA laptop after reinstalls

Hi, I am trying to help a friend who's laptop's audio stopped working after a simple lid close. the symptoms are almost the same as posted in this thread years ago- No Audio Output Device Installed.
I'm deeply worried for him after reading the thread.
things I tried over the last few days are...

1. All the usual downloading ,reinstalling etc as per above thread.
2.Restore, Reset
3 Installed 1809 version
4 Reformatted and changed partitioning to MBR - Sound came back even after 1st reboot but alas reverted to "No Sound" the next day
5 Reformatted again, this time not getting any updates - "no sound"
6 Cleaned Registry - sound came back so I done a System Backup ( wasn't able to return the Backup) anyway Sound fail again on 1st reboot
7 Installed an old version of Win 7 to see if that worked - Sound didn't work till I tinkered with a few things -when working here I noticed that it was the generic or MS sound that was working (no Realtek).
8 After this I figured I might as well persevere with Win 10 but after much more Reformatting (finally opting to change back from MBR Partitioning) I still can't get the sound back.

Now I'm nearly giving up but have updated Win 10 hoping a fix would be in the update alas 'No"

I have downloaded some UAD Realtek Drivers which I am about to load.

Sorry for the long post, I am not PC Savy but just s'one with a little more experience than my friend , If anyone has any good ideas I'd love to try them!

Anyway Regards Everyone!

Vimy

Thanks for reply, I won't be online for a few days as I'm changing Service Provider. but yes I've tried that. I think i's a registry issue because after many fresh installs, my problem remained and became apparent after rebooting. Later reinstalls didn't seem to fix anything. I cannot now get a PCI Data Acquisition and Signal Controller to function which might be blocking the audio drivers from properly installing. either that or a UAA Bus Driver problem, I'm not totally sure because These may have been inactive/ missing (from a Win 10 update) before he gave me the PC.

Just a general question about the Registry that someone here might be able to help me with.
Is there a way to default the registry to a state that it was in before any OS was loaded?
What would happen if I take out the memory sticks in the laptop?
Where is the Registry located?
I may be probing the wrong avenue here but I think the sound card itself is ok, even the drivers for it are ok, as The sound worked on three occasions( after various Reinstalls) alas until restarting.

Anyone got any tips?

Vimy

You kept on saying sound came back and then no sound the next day.

You close the laptop lid and then no sound.

It probably means that you have old realtek driver that has some sort of power management bug --- i.e. the sound chip won't come back awake after your laptop went to sleep when you close the laptop lid.

Thanks for your input!
interesting view, but the fact that the driver seems never to fully install , until I completely wiped the drive the first time and changed the partition system to MBR so i'm thinking the registry had no memory of misplaced data. And with later reinstalls there must have been leftover settings in the registry as (I think) it has its association with the RAM/ROM or BIOS.

You wrote a lot of sentences --- yet there is really zero information provided for us to give you any advice.

sandyt said:

You kept on saying sound came back and then no sound the next day.

You close the laptop lid and then no sound.

It probably means that you have old realtek driver that has some sort of power management bug --- i.e. the sound chip won't come back awake after your laptop went to sleep when you close the laptop lid.

Hi Sandyt

If a driver has a bug as above, how could it still remain after 3 fresh windows installs? would you think the problem has to be either in the PC Memory or the Registry?

Vimy said:

Hi Sandyt

If a driver has a bug as above, how could it still remain after 3 fresh windows installs? would you think the problem has to be either in the PC Memory or the Registry?

If the driver has a bug and you kept on reinstalling the same driver --- of course the bug remains.

If you think that it is a registry problem, you can back up all the data and then wipe the drive and completely reinstall the OS. I think it would not solve your problem.

You write a lot but you give zero information.

What is the bios version? What is the driver version? Why are you reinstalling 1809 when 1909 is available? What did the device manager looked like? Is it that the audio device is completely missing? Is it that the audio device is present but has a yellow exclamation mark?

- - - Updated - - -

My suggestion is that you give the laptop back to your friend because the problem exceeds your technical capabilities and you will cause more problems than solving them.

If the driver has a bug and you kept on reinstalling the same driver --- of course the bug remains. No- Different drivers were installed each time

If you think that it is a registry problem, you can back up all the data and then wipe the drive and completely reinstall the OS. I think it would not solve your problem. Yes and no , done that three times different outcomes

You write a lot but you give zero information. - I pointed to a thread from years ago with the same problem, there hadn't been any success there ,maybe i'm in the wrong place

What is the bios version? - latest.
What is the driver version? - latest on Asus ,latest on Realtek.
Why are you reinstalling 1809 when 1909 is available? - In case the problem came with an update.
What did the device manager looked like? No audio drivers present , HD Audio controller greyed out and hidden at various reinstalls.
Is it that the audio device is completely missing? yes, but sometimes it showed but I could never get the device drivers to function, either from not being fully installed, disconnected or failing to start.
Is it that the audio device is present but has a yellow exclamation mark? sometimes.

- - - Updated - - -

My suggestion is that you give the laptop back to your friend because the problem exceeds your technical capabilities and you will cause more problems than solving them.
- good advice, but not many people will help without getting paid, I admire people like you who at least try to help strangers. My friend has his machine back running Win 10 ver. 1909 with no sound, please don't offend me for trying to help!