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You’re muted – or are you? Videoconferencing apps may listen when mic is off

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Re: You’re muted – or are you? Videoconferencing apps may listen when mic is off

#51
post #17

My team and I built some of the world's most decentralized videoconferencing software, using WebRTC. You can try it on https://yang2020.app/meeting for example ... but it's available in all of our apps, including for teachers, etc. Since a major point of our platform (qbix.com/platform) is to avoid relying on external third parties, that meant we built a version of livestreaming that is completely peer-to-peer. Imagi…

2) Seems like a waste of bandwidth, did you consider the use case that turning off the video stream might be done to try to reduce bandwidth usage either due to cost of bandwidth or bandwidth being limited enough to break other simultaneous needs? And since 3) while creepy, is at least done on the client so does not seem to require the stream to always be sent to the other clients.

Re: You’re muted – or are you? Videoconferencing apps may listen when mic is off

#52
post #22

Earlier quoted context omitted.

Most MacBooks are also designed so the camera “on” light is impossible to disable in software.

Some hardware up there must be active and sending data even when the light's not on. It's how they make the (excellent, can hardly live without it now that I'm used to it) automatic monitor color temp adjustment work, AFAIK. Though maybe that's a separate sensor from the camera proper.

The camera and microphones are run through the T2 security chip. Also, there's a separate ambient light sensor.

Re: You’re muted – or are you? Videoconferencing apps may listen when mic is off

#53

I feel like they're trying to make an insidious suggestion about the usage of these. IMO, there's likely a good reason - user experience. At a hardware level, grabbing the microphone can take time. Even worse that timing is inconsistent across devices, workloads, etc. That leads to a bad experience when unmuting and needing to delay your commentary. The solution to this is to keep the microphone on, but mute at a sof…

The worst part is that on iOS you can't just start and stop input stream separately from output, but you have to stop the entire audio session and restart it in output only category. You can configure the session to ignore all input channels, but that won't get rid of the mic indicator (or at least didn't back when the mic indicator was introduced in the first place).

Yes, I work on an app that keeps the mic running all the time because of the above, and because ASIO doesn't allow disabling input at all.

Re: You’re muted – or are you? Videoconferencing apps may listen when mic is off

#55

I feel like they're trying to make an insidious suggestion about the usage of these. IMO, there's likely a good reason - user experience. At a hardware level, grabbing the microphone can take time. Even worse that timing is inconsistent across devices, workloads, etc. That leads to a bad experience when unmuting and needing to delay your commentary. The solution to this is to keep the microphone on, but mute at a sof…

got a modmic - popular mic - has a button on it to mute the mic- light turns red - pushed the button and went for a pee - came back to the meeting - left again to get a drink - came back - was asked to mute my mic - light was red - clicked hardware button - red light turned off - clicked again - right light turned on - mic was still active - no longer trust hardware buttons

That is a button that works via software, not a physical disconnect like on some other mics. When its a physical disconnect the os can’t tell if you’ve sent a mute command, just that all audio input stopped.

Re: You’re muted – or are you? Videoconferencing apps may listen when mic is off

#56

I feel like they're trying to make an insidious suggestion about the usage of these. IMO, there's likely a good reason - user experience. At a hardware level, grabbing the microphone can take time. Even worse that timing is inconsistent across devices, workloads, etc. That leads to a bad experience when unmuting and needing to delay your commentary. The solution to this is to keep the microphone on, but mute at a sof…

It’s something to be aware of.

The first time I had ever heard of Zoom, it was long before the pandemic and it was about how Zoom was a videoconferencing app that was installing an http server (read, a security hole on the user’s computer) which remained even if you deleted the app. This was to “improve the user experience” so that it could quickly reinstall itself if you clicked one of their web widgets to start a call.

It’s worth checking in on exactly what software is doing in the background, auditing its activity and coming to a more precise understanding of 1. The reputation of the company behind it and 2. How they came to have this reputation and whether it is still relevant.

Re: You’re muted – or are you? Videoconferencing apps may listen when mic is off

#57
post #44

> “With a camera, you can turn it off or even put your hand over it, and no matter what you do, no one can see you,” says Fawaz. “I don’t think that exists for microphones.” Maybe it doesn't exist on whatever sleek glassy slabs they're working with, but the old Thinkpad, Elitebook, and Precision workstation laptops I have around me at the moment all have dedicated microphone mute buttons (the Precision has a Fn key c…

On my Thinkpad, this was still just interpreted as an OS-level keyboard shortcut, as far as I remember. A solution that actually (logically if not physically) deactivates any built-in microphone would arguably be at least as important as a "webcam shield". Apple does this for the built-in microphone for their newer laptops, but that benefit is immediately negated when e.g. connecting a USB webcam that also contains a…

Yes those mute lights have been stuck on "lit" (= "mute") on my Windows forever, both the mic and speaker lights. However recording and playback work fine, the lights just stay on. Very annoying, a little unsettling.

My daily driver is Ubuntu where both lights work fine, on the same machine (dual boot). But now I know not to trust them.

Lenovo ThinkPad P51

Re: You’re muted – or are you? Videoconferencing apps may listen when mic is off

#58
post #17

My team and I built some of the world's most decentralized videoconferencing software, using WebRTC. You can try it on https://yang2020.app/meeting for example ... but it's available in all of our apps, including for teachers, etc. Since a major point of our platform (qbix.com/platform) is to avoid relying on external third parties, that meant we built a version of livestreaming that is completely peer-to-peer. Imagi…

2) Seems like a waste of bandwidth, did you consider the use case that turning off the video stream might be done to try to reduce bandwidth usage either due to cost of bandwidth or bandwidth being limited enough to break other simultaneous needs? And since 3) while creepy, is at least done on the client so does not seem to require the stream to always be sent to the other clients.

Well, yes, it can be turned off and yes it can be not sent, but that's at the discretion of the client. They can "hack their client" to send it anyway which is why everyone has to "refuse" to receive it from a "muted" client, as well. It's a second line of defense. Never trust the client.

Re: You’re muted – or are you? Videoconferencing apps may listen when mic is off

#59
post #6

Earlier quoted context omitted.

What about those cases where you wish you'd been muted? "Hey everyone can hear you, did you want me to erase the last 5 seconds from their memory?" would be a nice feature. Facepalm.

There's a Zoom setting to Mute Attendees Upon Entry. I make that my default for every meeting. Some people complain, but I've had way too many people join and not realize their mic is live, so the meeting is interrupted by random dude shouting at his children to stop making noise, etc. Or even better, when the meeting tool has a "Call me at this number" tool, but does not require validation before bridging the audio.…

Huh, isn't this the default behavior? I never set that and all meetings I attended mutes me by default

Re: You’re muted – or are you? Videoconferencing apps may listen when mic is off

#60
post #46

Earlier quoted context omitted.

Couldn’t this be done by using some ML on the video stream?

That's way more computationally expensive and only available if the camera is on (and the user's mouth is visible).

That’s true. I’ve never tried it with the camera off.
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