I just got a new laptop (ASUS GX501G), and Ubuntu 19.10 is having sound problems. It will not play sound through the speakers or through the headphones. The microphone does not work either. In the 'Sound' portion of the settings, it seems to be recognizing the speakers as an output device properly. Additionally, when I plug in headphones or connect a bluetooth speaker, it recognizes the device change and swaps the icon, name, and settings profile. When I dual boot back into Windows 10, the sound works as expected.
Strangely, the speakers will work briefly for roughly 2-3 seconds after I disconnect a bluetooth headphone device. The bluetooth headset powers off and the speakers play music while it decides where to route the audio next.
I have tried opening alsamixer in the terminal and raising the volume and un-muting the different channels with no success.
Another very odd thing: when I plug in my over-the ear headphones it is picking up a very faint signal to a local Mexican radio station, not sure of the exact frequency or if it's FM or AM. The high production value makes me guess FM. I've never experienced that in a computer before...
PulseAudio driver and RealTek chips do not cooperate except for the known sound bursts during mode changes. I had to replace a 15 year old ASUS motherboard (that was working fine under 19.04 with a 5.1 system) with a current ASUS motherboard and, of course, the audio stopped working. The speakers are idle but other USB audio and the HDMI monitor speakers work fine.
BTW, all radio wave receivers transmit too (albeit on a different frequency) depending on electrical characteristics. One of the reasons why portable electronic devices had to be shutdown during takeoff/landing as a precautionary step. What these devices transmit is anybody's guess?