I have an Acer Aspire X-605 with Windows 8.1 and I was experiencing the same issue when my TV display turned off.
Updating to the latest BIOS (BIOS_Acer_P11.A3_A_A) and updating to the latest drivers didn't fix it.
The old driver mentioned previously fixed it for me though.
Nikkel wrote:
hi everyone!
I have FIXED my problem with HDMI audio always disappearing when I turn off either my TV and/or amp.
Step 1: Restart your computer so the audio is working again
Step 2: Install Win_seven64_Intel(r) Graphics Media Accelerator Driver 15.31.17.64.3257 (google it)
(The file contains both version 9.18.10.3257 intel HD graphics driver & 6.16.0.3112 intel Display audio driver)
I tried updating my bios/installing every different driver package I could find/installed all the windows updates to no avail, however, only this package fixed the problem. My setup is PC onboard hdmi->amp (pass thru)->plasma TV, Win7 pro x64 SP1, i3 4130T (HD 4400), Gigabyte b85m-hd3.
I am unsure if this package/driver version will fix other integrated intel HD series graphics cards audio problems but it's worth a try.
Spread the word if this works for you GL!
The only place I could find the driver was here:
Redway3d - Windows 7 64 bits - Intel(r) Graphics Media Accelerator Driver 15.31.17.64.3257
I gave it a scan with VirusTotal - Free Online Virus, Malware and URL Scanner then proceeded to install it.
Step 1 above is crucial because when I ran the installer without restarting it only said it was going to overwrite the Display Driver and not the Audio one.
I think Windows Update updated the drivers shortly after so I had to do the install process again.
I can't work out how to have Windows Update ignore updates to these two drivers and still check for updates to other drivers though.