Make laptop speakers and external speakers work simultaneously

[Promios]

I have an Asus ROG Zephyrus G14 GA401QM with Windows 11 Pro.

When I plug in my external speakers to the headphones jack, my laptop speakers turn off and the sound goes to the external speakers. I know how to switch the sound to a laptop or external speakers, but can't find how to make them sound simultaneously. I could get much better sound quality this way.

I checked various advice like updating drivers, showing hidden devices, making one or another device the default output device, etc., but nothing has helped.

I would highly appreciate your advice.

[azwxguy]

Can't say for certain, but for like forever headphone jacks have always mechanically disconnected the output from internal speakers in favor of the connected device. Years ago, I remember a hack to a 3.5 mm headphone jack where you could use a file to remove a portion of the jack barrel where it would still make contact but wouldn't disconnect the internal speaker route. This was way before the internet, so probably not searchable.