ACER Aspire E5-721-492D HDMI not transmitting sound to HDTV.

tarantzilla

I am using an ACER Aspire E5-721-492D laptop/notebook, part number NX.MNDAA.003. (Yes, it’s a legacy machine made in 2014. See its Datasheet for more details if you really need them.) I have it set up as a dual boot machine with Windows 8.1 and Kubuntu 20.04. And it is connected to a 40", Samsung HDTV with a standard HDMI cable.

When I boot Kubuntu and play some media file (e.g., James Cameron's Avatar) with some media program (e.g., VLC), the system works perfectly. I.e., I can view the movie in full, living color at 1080p with full stereo sound through the HDTV. How do I know? Clicking the mute button on the TV’s remote works. (Read this to mean that the hardware is working perfectly.)

When I boot to Windows with the TV off, the laptop boots to the computer’s screen. And if I play the same media with the same program, the system apparently works as expected, i.e., 1080p on the laptop's screen, and with stereo sound coming from the laptop’s speakers. (The TV’s remote has no effect, as expected.) (Read this to mean that the hardware is still working perfectly.)

If I don’t change anything from the previous paragraph (i.e., the laptop's lid/screen is left open), except turn the TV on before I boot the laptop, the laptop does not acknowledge that the TV is even there. The TV remains blank and without any sound. And Windows doesn’t show an HDMI device anywhere in Device Manager’s listing. (PnP, or its analogue, didn’t work.)

Note that the same is true if I wait till after it has booted Windows before I turn on the TV.

When I boot to Windows with the TV on, and the lap’s lid/screen closed and off (i.e., automagically turned off because it's closed), the laptop boots to the TV. And if I play the same media with the same program, the video display on the TV is as expected, but the sound is not being passed to the TV via the HDMI system. (The TV’s remote has no effect.) The sound, however, is being misdirected through the laptop's speakers.

Bottom line (to avoid confusion on the parts of the audience): Even though I've proven that the hardware is in good shape, regardless of what else I do with Windows, some part of its audio software (e.g., drivers, sound card, video card, something else) is broken, and will not communicate with the HDMI system, and therefore I get no sound from the TV.

I have tried fiddling with Device Manager’s "Audio inputs and outputs," and “Sound, video and game controllers” categories, trying to update, disable and even uninstall alternately, both Microsoft’s "High Definition Audio Device" and the "Realtek High Definition Audio" entries. No joy!

So, what do I do? Is there a way to fix this? Or must I reboot to Kubuntu every time I want to watch a movie? (Linux is looking better and better as time progresses!)


Thank you, one and all, for reading through this too long dissertation/diatribe!

Thread was edited to add model name to the title

tarantzilla

This promises to become another long post, but I'll try to be as brief as I can.

Both Joe9844 and Billsey, thanks so much for your input. Here's what worked.

Billsey first...

"You need to select the HDMI port as your audio output device in Sound Settings. It's likely defaulting to the internal speakers."

There was no HDMI port or any mention of HDMI anywhere in the Device Manager. Apparently, Windows' generic "High Definition Audio Device" doesn't acknowledge HDMI's existence, and Windows' generic display adapter addresses the HDMI video signal generically, but fails completely to transmit a sound signal. No joy here!

But then along came Joe9844 (actually he preceded Billsey, but I'm not keeping score here) with his suggestion that, "You need a audio driver from your graphics card manufacturer (which is bundled with graphics driver)."

Okay, but I thought I already had one. Maybe two, actually: Window's generic plus one from Realtek. So I went back to the Acer Datasheet and studied it carefully. Whereupon I realized that the video adapter that I needed to use wasn't necessarily Realtek's, but rather one put out by AMD.

So I hunted up the correct software on AMD's website (Support and A4-6210 with RadeonT R3 Graphics Drivers & Support), and downloaded and installed the appropriate drivers.

Bingo! Now I have great stereo sound coming through the HDMI cable and emanating from the TV.

Oh, oh. There's a problem. All the movies and videos that I try to play with VLC via the HDMI cable have a wide, brilliant, green band across the bottom 1/3 of the screen, and the actual image is squished into the top 2/3 of the screen, and the quality is so bad that it can't be watched without massive migraines.

So I went to Videolan's forum and posted another of my epic queries. I'm taking the liberty of posting a link to someone else's forum (A) Because they're not operating in direct competition to this one. (B) So others with this same problem won't have to go through the same ordeal I did. May the moderators be kind to us all!

I got a quick answer that solved that problem involving a very simple adjustment of VLC's settings. So now I can binge-watch all my movies and videos without going red-green blind, or throwing an empty beer bottle through the TV screen! Life is good again.