As I posted this question, the Ubuntu 16.0.4 LTS I am using is freshly/newly reinstalled, little problem is that the sound is not working properly, when I tried to test it out, System Settings > Sound > Speakers (Built-in Audio) > Test Sound, then I test both the Front left and Right left, here are the results:
- Front left - working but not working as it should be, I do not know the specific term but the sound it's creating is not good in the ears.
- Front right - not working at all.
What do I need to do make the speakers works?