Previous discussions about this motherboard advise that speaker output for onboard audio codec ALC1220 is not restored correctly when system is booted
A Manjaro user with same motherboard found a workaround to reset the speaker control in ALSA
amixer --card=0 sset Headphone 100% unmute
No Sound (Temporary Fix) alsamixer MSI Ge75 Raider
Another workaround for this motherboard was confirmed to work in Linux Mint forum
[Laptop] No sound from built in speakers - Linux Mint Forums
linux mint cinnamon 20 no sound until plugging headphone - Linux Mint Forums
Edit PulseAudio configuration for speaker output
sudo nano +102,10 /usr/share/pulseaudio/alsa-mixer/paths/analog-output-speaker.conf
Change this section:
[Element Headphone]
switch = off
volume = off
To this:
[Element Headphone]
switch = off
volume = merge