andoid tablet headset audio speaker tts

Hello,
I have an android pc, ODROID X2 connected though hdmi to a touchscreen with built in speaker.
Here is what I want to do :
Have my audio playing though the headset out on the board (green jack) and have my navigation instruction through the built in speaker in my touchscreen.
What I have:
every sound comes out on both speakers : through the screen speaker and through the audio output on the board.

I tried different settings in sound about with no differences.
I tried to connect the screen through the hdmi/vga adapter with audio output on the adapter and connected an amplified speaker : no differences : every sound goes through both speakers.

My screen is attached through a micro hdmi connector on my board.

Any ideas / suggestions?

Thanks

Hello,
Anybody can help?
Thanks

If SoundAbout is installed it should detect the headset being plugged in. Normally the Aux Digital (HDMI) would be disabled when using a wired headset.

It's odd that the audio is coming out of both the wired headset and HDMI connections.

For Navigation, if it uses Text to speech, you can set the SoundAbout Text To speech audio to use "Aux Digital (HDMI)".

This thread shows switching Text To speech to Bluetooth, but it's similar:
https://soundabout.forumotion.com/t202-navigation-text-to-speech-audio-to-various-outputs-bluetooth-mono-in-car

Yes,
The sound comes out of both connections. When i plug in or out the wired headset there is no difference in the behaviour of soundabout.
And i don't have an icon when i plug in the headset no matter if i check or uncheck the the detection of the headset in soundabout.
by the way, i have become a beta tester and i bought the app in playstore.
Maybe it is an issue with my android board...
thank you and I wait for more suggestions if it is possible