Yous should consider updating system BIOS
https://www.dell.com/support/home/en-uk/product-support/product/g-series-15-3579-laptop/drivers
System data is showing 2 incompatible sound servers running
Sound Server-3: PulseAudio v: 15.0 running: yes
Sound Server-4: PipeWire v: 0.3.40 running: yes
PipeWire cannot support audio unless PulseAudio is removed and replaced, but it can impede PulseAudio functions.
Install metapackage manjaro-pipewire to remove and replace PulseAudio packages
To continue using PulseAudio without PipeWire use this command to stop, disable and mask PipeWire service and socket
systemctl --user disable --now pipewire.socket pipewire.service && systemctl --user mask pipewire.socket
Onboard audio device Intel Cannon Lake PCH cAVS is using legacy driver snd_hda_intel instead of the Sound Open Firmware driver to support internal digital microphone array
Check that package sof-firmware is installed for the Sound Open Firmware driver sof-audio-pci-intel-cnl
If you have resolved those 3 issues and audio is still not working as expected, please post full system information
inxi -Fazy