[Bug]: Audio input in Ubuntu guest gets muted with VM audio controller "Intel HD Audio" #559
Description
Version
7.2.6
Host OS Type
other
Host OS name + version
Ubuntu 22.04 / Ubuntu 24.04 / Windows 10
Host Architecture
x86
Guest OS Type
Linux
Guest Architecture
x86
Guest OS name + version
Lubuntu 22.04.5 LTS
Component
Audio
What happened?
Guest applications (using pulseaudio) capture silence when VM audio settings are as follows: both input and output enabled, choosen controller is "Intel HD Audio". At the same time it's possible to capture normal audio signal by either using ALSA hardware device directly or by toggling mute/volume after recording stream started. And this action temporarily "repairs" pulseaudio capture until pulseaudio daemon suspends source after few seconds of inactivity (e.g. you have to repeatedly run audio recordings or keep opened Volume Control app with input signal indicator).
Somebody already reported this issue on old bugtracker: https://www.virtualbox.org/ticket/22347. Its author claims that bug appeared after version 7.0.14, but I wasn't able to check this version because of painfull problems with installing on my modern Ubuntu 24.04.
How can we reproduce this?
On host machine with working microphone edit VM settings by checking both Audio Output and Audio Input and choosing Audio controller "Intel HD audio", then start VM to boot from LiveCD.
Test1. Open terminal, start recording with command "parecord --file-format=wav test.wav", talk something, interrupt with Ctrl+C. Play file with command "paplay --file-format=wav test.wav" and you hear nothing.
Test2. Prepare second terminal tab with command "pacmd set-source-mute 1 1 ; pacmd set-source-mute 1 0", run in first terminal same command as in Test1, then in second terminal run prepared command, then talk something, and then in first terminal interrupt recording. Now with playing of this file you'll hear audible sound. Quickly repeat Test1 and now it succeeds. Wait 15 seconds and repeat Test1 - it fails.
Test3. Run command "pasuspender -- arecord -D "hw:0,0" -c 2 -f S16_LE test.wav" and interrupt it. Quickly repeat Test1 and now it succeeds. Wait 15 seconds and repeat Test1 - it fails.
Change VM audo settings by choosing default audio controller (ICH AC97) and all tests will succeed.
Did you upload all of your necessary log files, screenshots, etc.?
- Yes, I've uploaded all pertinent files to this issue.