Sometimes manual intervention on various Linux system's, including Debian, is required to fix things after waking up from sleep.
One persistent issue is the sound system / pulseaudio needing to be reset and not working until you do that after waking up. It's not clear if it's an OS issue itself or the sound driver, but this will fix things.
Where do we put scripts or commands that need to be used upon wakeup automatically?
/lib/systemd/syst........
If your audio is not working and you got this in your syslog:
pulseaudio[13710]: [pulseaudio] sink-input.c: Failed to create sink input: too many inputs per sink.
The issue is generally caused by too many audio inputs, or in other words you have too many applications that are hooked into pulseaudio.
An easy and notorious offender is by having dozens of Firefox browser tabs open.
Solution:
Close all of your Firefox and the problem will........
Here is the scenario, you are using QEMU/KVM and are using something like the AC97 sound driver to pass the host audio to the guest via pulseaudio. This is useful because you can transparently pass your mic input from the host which means you can mute your microphone from the host, which prevents the guest from receiving any mic input even if unmuted.
Mute / Unmute Fix
This issue also seems to happen even if you press the mute button on the microphone and then unmute,........
Volume control will often stop working, if your sound server (normally pulseaudio) dies or restarts whether by itself or by you. The reason pulseaudio may need to be restarted is due to some sort of crash or other issue that prevents sound from working (normally restarting or doing a killall pulseaudio fixes things).
However, you will normally find at least in OS's like Ubuntu/Mint 16/18+ that you cannot control the volume whether adjusting the level, changing input/outputs and........
Pass QEMU this flag:
-soundhw ac97
Or you could use (for a Ensoniq soundcard):
-soundhw es1370
However on some machines I get this error:
pulseaudio: pa_simple_new for capture failed
pulseaudio: Reason: Connection terminated
pulseaudio: pa_simple_new for capture failed
pulseaudio: Reason: Connection terminated
audio: Failed to create voice `ac9........
What this really refers to is gnome-volume-control-applet which is what controls the volume in the panel/indicator applet.
In Ubuntu 10.04 it is just the applet mentioned above, run that from the command line and it will start.
I lost mine when I removed pulseaudio trying to fix audio issues with Flash and Opera. It also removes the gnome-volume-control-applet from starting. *Ialso note........