No mic level on Debian VirtualBox

I have set up a minimal Debian system in VirtualBox (using the netinst) and installed Mycroft using the git clone method. I am using ALSA and don’t have pulseaudio installed. I have adjusted the output volume and capture in alsamixer and can use arecord and aplay to record and play back sound successfully.

If I start Mycroft using ./ debug, I can hear when Mycroft speaks e.g. if I type What time is it?. However I have no mic level showing in the CLI and Mycroft doesn’t respond to the wake word (the default ‘Hey Mycroft’).

I have the following in ~/.mycroft/mycroft.conf:

  "play_wav_cmdline": "aplay %1"

I’ve tried changing this to

  "play_wav_cmdline": "aplay %1",
  "listener": {
    "device_index": 0

but it doesn’t seem to help.

I’m trying to avoid installing pulseaudio if possible but can do this if necessary.

Any help would be gratefully received!


hey, this happened to me before, i needed to have the mic plugged before i launched the vm or it wouldnt recognize it

Thanks @Jarbas_Ai. However I’m using the internal mic on my MacBook Pro, and it’s recognised by the VM as I can record a wave file using arecord and play it back successfully using aplay.

I found the same thing running a VM of Mint in my laptop. … the built in audio would only work as input ( or output) I plugged a cheap usb soundcard in ( allowed Virtual box to access it) and then set IT as input for the mic in the VM and it all works like that…
My guess is that the VM cant (always?) map the builtin sound card as a fully duplex device, which mycroft seems to need.
(edit) to be clear here the audio output goes to the built-in speakers, and the mic input goes via an external usb soundcard

Thanks @a_user. I’ll give that a try when I get a chance.

Your comment about full duplex led me to do some testing. I can play an MP3 file in one shell and record a wave file simultaneously in the other, then play this wave file at the same time as the MP3 is still playing. I presume this means that the VM is able to use the built-in audio correctly.

fair enough… It is just what I found for me running on a VM of Linux-Mint. , and your symptoms are the same.
I just happened to have a £3 usb sound card floating around the fixed the issue.

Thanks for your help. I’ll give an external sound card a try.

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