How to play audio via both HDMI and audio jack?

Hello, I'm Jan and I'm happy to help you today. I'm sorry that you are experiencing these problems. I recently have this feedback loop problem in the Stereo mix. Try to set the motherboard onboard audio/speaker/3.5mm out as your default audio output device, not any other available audio output device.

Right-click in the Speaker icon on your taskbar

Click Sounds

under Playback tab

Right-click on the onboard audio device/3.5mm out/headphones

then set it as the "Default device"

then in the Recording tab

Right-click in the stereo mix

open the Listen tab

check the listen to this device

Then select the "HDMI audio" as your playback device.

Also, try disabling all the mic devices in the recording tab.

The only solution I can think of now would be hardware based - e.g. an HDMI splitter with audio jack output, but these are not cheap.

I found one for under £20 so have ordered.

The device I ordered did not work as described, so I have sent it back.

Basically, it had a 3-switch mode: 5.1, 2.0, or passthrough. In passthrough mode the audio played through HDMI but not the other audio outputs. In the other modes, the audio played through the other outputs, but not through HDMI (though the video through HDMI was fine).

I found a similar-looking but different-brand device on a well-known site that allows asking questions of previous purchasers, one of whom confirmed that that device didn't work as anticipated either.

I want the audio to play through HDMI (along with video) AND a 3.5mm stereo jack AT THE SAME TIME - AND IN SYNC. We are more than 20 years into the 21st century. How hard can that be?

I want the audio to play through HDMI (along with video) AND a 3.5mm stereo jack AT THE SAME TIME - AND IN SYNC. We are more than 20 years into the 21st century. How hard can that be?

I know right? On macOS side this can be done through their built-in app and it's been around for1.5 decades with a release of macOS Leopard back in 2007. It's hard to believe that Windows OS still do not have this.

The only solution I can think of now would be hardware based - e.g. an HDMI splitter with audio jack output, but these are not cheap.

I found one for under £20 so have ordered. It is very disappointing that modern PCs and laptops running Windows are still not yet capable of such basic functionality. Maybe it's a limitation of the internal sound card, but I expect better than this. Companies are all too keen to sell you a new laptop because your old one is "outdated" but it seems the new ones are barely any better than those of almost 10 years ago.

Try to set the motherboard onboard audio/speaker/3.5mm out as your default audio output device, not any other available audio output device.

Unfortunately this does not work satisfactorily either. Whilst I do get the sound played through both output devices, there is a split-second but significant time lag between the audio played through the default device (external speakers via audio jack) and that rerouted via 'Stereo Mix' to the HDMI device, resulting in an echo and unlistenable sound.

Originally I had tried with HDMI as the default device and 'Stereo Mix' routing through the audio jack but this did not work at all (all I got was a very low bass hum through the the audio jack).

It is surely not beyond the realms of a decent operating system to be able to play audio through more than one device simultaneously, but this would appear to be something Windows is disappointingly completely incapable of. The only solution I can think of now would be hardware based - e.g. an HDMI splitter with audio jack output, but these are not cheap.