[Bug]: Guest OS grabs forbidden access to host microphone

[Elliria]

Version

7.2.4

Host OS Type

Linux

Host OS name + version

Kubuntu 24.04 LTS

Host Architecture

x86

Guest OS Type

Linux

Guest Architecture

x86

Guest OS name + version

Ubuntu 22.04 LTS

Component

Audio

What happened?

The guest OS grabs control of the host OS' microphone. Note that the microphone is disabled by default on my host system.

I happened to notice the little microphone icon in my host system's tray that was enabled while VirtualBox was running Ubuntu 22.04 LTS with these settings, which I use for Ubuntu and any of its derivatives:

• Base memory 8192
• Processors: 2
• Video memory: 128 MB
• Audio: enabled (default settings)
• Network: enabled (default settings)
• USB: disabled

You can see the microphone icon just to the right of the sound icon in my system tray:

When I hover over it with my mouse, it displays a pop-up that says:

Microphone
ALSA plug-in [VirtualBoxVM] is using the microphone

I can't seem to capture that pop-up with Kubuntu's screenshot program. Sorry. I copied it exactly here, though.

Here are the audio settings for the Ubuntu 22.04 LTS virtual machine:

Here's the log:

VBox.log

Interestingly, the issue does not exist for my Ubuntu 24.04 LTS virtual machine with identical settings.

I plan on testing Kubuntu 22.04 LTS and Kubuntu 24.04 LTS in VirtualBox in the near future and will update this issue if the microphone appears for either or both of those.

Last, but not least, this seems to be a known issue: issue #19527 in your forums

Feel free to let me know if there's any further information I can provide.

How can we reproduce this?

Method 1:

1. Create a virtual machine for Ubuntu 22.04 LTS, giving it 8192 MB of base memory and skipping the auto-installation offered by VirtualBox.
2. Run the virtual machine you just created.
3. Choose to try or install Ubuntu when the operating system has booted.
4. You should immediately see a disabled microphone in the host system's tray.
5. Shut down the virtual machine. The microphone icon will go away automatically.

Method 2:

1. Create a virtual machine for Ubuntu 22.04 LTS, giving it 8192 MB of base memory and 2 CPUs and skipping the auto-installation offered by VirtualBox.
2. Go into its settings and adjust any that need it to match these:
   • Base memory 8192
   • Processors: 2
   • Video memory: 128 MB
   • Audio: enabled (default settings)
   • Network: enabled (default settings)
   • USB: disabled
3. Run the virtual machine and install Ubuntu. Note that your host machine will instantly have a disabled microphone icon in its system tray.
4. Shut down the virtual machine after the installation is finished. The microphone icon will go away automatically.
5. Now, any time you run that virtual machine, you should immediately see an enabled microphone in the host system's tray.

Did you upload all of your necessary log files, screenshots, etc.?

• Yes, I've uploaded all pertinent files to this issue.