Thanks for the reply.
The hardware has enough computational power: Under Batocera, the 3D graphics is fluid while emulating the N64 and Doom.
It do run Amiga 4000 68x060 by winUAE under windows7 where Doom works excellently.
As you suggest, the limit can be into the PC itself. system. At this point, if we exclude a lack of hardware power, it remains to investigate on how the Hardware is driven.
In fact, the background sound is perfectly played before emulation start.
Another hint: before copying roms and bioses, the sample games included with batocera was not affected by the audio issue.
This problem began after inserting roms and bioses.
Concerning the different settings, I followed all instructions available on the web for solving audio issues: kodi setting analysis, change audio settings, try to include instructions on boot file to change pen mode, etc..
Concerning the peripheral, I tried to change the USB port of the batocera pen drive, the port of the mouse, the Bluetooth keyboard, etc. I tried to display the screen on the laptop monitor and on a secondary monitor connected the VGA port. Briefly,
I tried all the permutations for the combinations of connected peripherals.
Do you have info on how to change audio driver ?