Hi Dell G3 (DMI: Dell Inc. G3 3590/0201H1, BIOS 1.6.0 08/08/2019) with the same issue (internal mic doesn't work, with external headset works)
~$ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 18.04.4 LTS Release: 18.04 Codename: bionic
~$ uname -a Linux ws165 5.3.0-61-generic #55~18.04.1-Ubuntu SMP Mon Jun 22 16:40:20 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
~$ arecord -l **** List of CAPTURE Hardware Devices **** card 0: PCH [HDA Intel PCH], device 0: ALC3254 Analog [ALC3254 Analog] Subdevices: 0/1 Subdevice #0: subdevice #0 card 0: PCH [HDA Intel PCH], device 2: ALC3254 Alt Analog [ALC3254 Alt Analog] Subdevices: 1/1 Subdevice #0: subdevice #0
Hi Dell G3 (DMI: Dell Inc. G3 3590/0201H1, BIOS 1.6.0 08/08/2019)
with the same issue (internal mic doesn't work, with external headset works)
~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 18.04.4 LTS
Release: 18.04
Codename: bionic
~$ uname -a
Linux ws165 5.3.0-61-generic #55~18.04.1-Ubuntu SMP Mon Jun 22 16:40:20 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
~$ arecord -l
**** List of CAPTURE Hardware Devices ****
card 0: PCH [HDA Intel PCH], device 0: ALC3254 Analog [ALC3254 Analog]
Subdevices: 0/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 2: ALC3254 Alt Analog [ALC3254 Alt Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0