2000194 - navigator.mediaDevices.enumerateDevices() incorrectly showing macOS Multi-Output Playback Device in list of audio inputs

Status: UNCONFIRMED

(Core :: WebRTC: Audio/Video, defect)

Description

[Jamie W]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:145.0) Gecko/20100101 Firefox/145.0

Steps to reproduce:

1. Set up a macOS Multi-Output device
2. Pre-requisite - call getUserMedia() and check Remember, so enumerateDevices() returns all devices
3. Call navigator.mediaDevices.enumerateDevices()

Actual results:

In the response of enumerateDevices(), observe that the Multi-Output device appears twice, first as kind="audioinput", as well as kind="audiooutput"

Expected results:

The Multi-Output device shouldn't be visible as an "audioinput"

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::Widget: Cocoa' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Stephen A Pohl [:spohl]]

I believe Core:Audio/Video is a better component for this, but please let me know if this is actually handled on the widget side. I didn't think it was.

Comment 3

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:jimm, could you have a look please?

For more information, please visit BugBot documentation.

Comment 4

[John Lin [:jhlin][:jolin]]

It's getUserMedia. Moving to WebRTC: Audio/Video.

Comment 5

[Jan-Ivar Bruaroey [:jib] (needinfo? me)]

Hi Jamie, I'm not able to repro using https://jan-ivar.github.io/dummy/enumerate2.html. After pushing Start Mic! I see:

    Cameras: 1
        ""
    Microphones: 2
        "AirPods"
        "MacBook Pro Microphone" (chosen)
    Speakers: 3
        "AirPods"
        "MacBook Pro Speakers"
        "Multi-Output Device"

...which is expected. No Multi mic shown. Does it repro for you with that link? If so, what does it output?

Comment 6

[Jamie W]

I can repro it using that link

    Cameras: 1
        ""
    Microphones: 4
        "Record Out"
        "MacBook Pro Microphone"
        "BlackHole 2ch"
        "Microsoft Teams Audio Device"
    Speakers: 4
        "Record Out"
        "MacBook Pro Speakers"
        "BlackHole 2ch"
        "Microsoft Teams Audio Device"

I am wondering if the BlackHole 2CH loopback driver, having stereo inputs and outputs, but being as part of the Multi-Output Device (which can only output audio, versus the regular macOS Aggregate Device), is what is making this trigger for me.

Comment 7

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:jib, could you have a look please?

For more information, please visit BugBot documentation.