Hello again,
this thread from the Manjaro forum made me think that you should also check the status of the pipewire-systemd-service after suspend, when you have the problem:
https://forum.manjaro.org/t/no-audio-after-suspend/78472/2
systemctl --user status pipewire
Edit: If you wish to switch from pipewire to pulseaudio to test if it works then, there was this post here in the forum: Switching between Pipewire and Pulseaudio