sound – Freak behiaviour of the sound card of my laptop

The sound card of my laptop sometimes runs after startup and sometimes not. I even tried to plug in the socket of my built-in 90 stereo amplifier or my headphones and nothing changed in the settings and no sound was starting to work.
Every time I launch Ubuntu, I see that the type and icon of the sound card change to another, while the output is sometimes normal, because it represents a headset or speakers In this case, I use my laptop connected to a 17 "4: 3 monitor via VGA) and other times, once I see a" dummy output. "for example, if I use it with the amplifier, it will show me the headphones because this amplifier will be recognized as a headphone.I have root access to the system, so i need to install diagnostics .. tools provided by you this is not a problem, the sound card is obviously the one integrated into my laptop.

My system specifications:

  • Notebook: HP 250 G3
  • OS: Ubuntu 18.10 cosmic
  • Core: x86_64 Linux 4.18.0-10-generic
  • Resolution: 1280×1024
  • CPU: Intel Core i5-4210U
  • RAM: 8 GB
  • VGA: built-in processor