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March 1

Can microphones be activated on PC, Macintosh? tablet? mobile?

Have a good day every body. It's well known that webcams can be activated without our will. Thinking about that brings me to other questions:
Q1) Is it the same thing about our microphones? Does the fact that we never hear or read about that subject means that really they can't be activated remotely?
Q2) If it is well this way, why webcams can be actived remotely even though microphones couldn't be activated remotely?
I propose a piece of answer for Q2): Webcams are digital when microphones are analog. But when we record our voice on a PC, the analog signal coming out off the microphone is then changed to a digital signal to be recorded on the hard disk. Which leads to Q3):
Q3) If the transformation analog-digital can be trigged remotely then the sound could be heard and recorded remotely. Is it so?
Q4) Is it the same with our tablets and our smartphones?
Q5) Do the Linux based-OS offer a better protection for our privacy?
I thank you for your answers and explainations.--Jojodesbatignoles (talk) 10:18, 1 March 2019 (UTC)[reply]

Microphones and webcams are under the control of software. This would be for tablets, phones, or laptops with built in microphones. Software can have a feature to enable remote control. The software will have to be installed somehow. This may be installed by the user or perhaps by malware, and malware will take advantage of bugs or a mistake on a user's part. To operate a microphone on a computer, the input is sampled and digitized. The rate and resolution is slightly flexible. The webcam image sensor does the same thing, but its pixels are inflexible. For Linux there would be less targeted malware than Windows, but also there may be more day zero exploits available unknown to you or the operating system maintainers. Graeme Bartlett (talk) 10:57, 1 March 2019 (UTC)[reply]

In general, hardware makers provide interfaces for their devices so that they can be controlled by software. The operating system controls who can uses these interfaces in what way - in an ideal world, this would only be possible via a controlled API which includes authentication (who is initiating the request) and authorisation (is that user allowed to do this?), and also would force e.g. the indicator light to come on whenever the camera or microphone is on. But we are not living in a perfect world. The Vault 7 documents e.g. revealed how the CIA can hack smart TVs and use their microphones for eavesdropping (and a smart TV is basically a computer with a built-in screen). In general, open systems like Linux may be less susceptible to attacks, and especially to intentional backdoors, since more people can and do look at the source code. But if you download and execute random code off the internet, you take your chances with any OS. If security is of prime importance, have a look at OpenBSD. But even they say Only two remote holes in the default install, in a heck of a long time!. --Stephan Schulz (talk) 12:20, 1 March 2019 (UTC)[reply]

Jojodesbatignoles, Linux is indeed more secure than Windows, but no software offers perfect security.

You should be aware that there are hardware solutions that cannot be hacked:

Microphone: Mic-Lock Microphone Blocker
Webcam: MySpyBlocker Webcam Cover
Cellphone: Mission Darkness Non-Window Faraday Bag for Phones

--Guy Macon (talk) 13:12, 1 March 2019 (UTC)[reply]

I would not trust the "Mic-Lock". On modern computers, you can usually pick the microphone via software, too. For webcams, a piece of gaffer tape or a post-it might be cheaper. And for the cellphone bag, I think a wrap in aluminium foil would be similarly effective, and much cheaper (especially for me - I just bough "some" aluminium foil to get into free shipping on Amazon without thinking too much, and I'm now sitting on 150m of the stuff ;-). --Stephan Schulz (talk) 13:43, 1 March 2019 (UTC)[reply]

Just the thing for making tin foil hats! :) I wish I knew how many laptops were able to select the built-in speaker when a speaker was plugged in to the microphone jack. It opens the wire to the internal mic on the one laptop I checked, but that's far too small a sample. --Guy Macon (talk) 04:36, 3 March 2019 (UTC)[reply]

How old was this laptop? AFAIK, since Intel High Definition Audio and derivatives replaced AC97 back in ~2004-2010 (okay I have no idea when the last devices which still had AC97 chipsets were sold but I think by 2010 they would be extremely rare), the norm at least on desktops has been to use ports which have an effective switch activated when something is plugged into the port and that signal to the chipset that something is plugged in. The software is then allowed to determine what to do. By the same token, the 'mic' port and 'headphone' or other ports are just recommendations/defaults. You're free to plug whatever you want into any port and good drivers or OS should let you select what is connected to that port. I thought on computers, ports which physically disconnect the connection to the other port or on board device died out with AC97. For phones, I don't know if they ever really existed except may be for very old phones since they've only ever had one port so what you plug into it is inherently unclear. Or if they did disconnect anything, it would be the speakers. Nil Einne (talk) 03:22, 4 March 2019 (UTC)[reply]

I notice sliding webcam covers are being given out as conference swag these days, like pens and usb sticks were some time back. Yeah I've also had doubts whether shorting the external mic input would necessary mute the internal one. I've considered attacking the internal one with a drill... 173.228.123.166 (talk) 06:39, 2 March 2019 (UTC)[reply]

I would imagine that a squirt of epoxy would stop the microphone element from vibrating. But maybe not; there might be some sort of seal to keep water out. --Guy Macon (talk) 04:36, 3 March 2019 (UTC)[reply]

I might try that, but they are tiny electret or MEMS microphones, so the epoxy might not affect them much. Further down this page I mention a crappy old phone I found. It might make a good "victim" for this treatment. Really though, whatever you do to silence the microphone in your own phone, someone else in the room is likely to have a phone in their pocket with its own microphone; there are likely other microphones in the room (in any laptops, and nowadays TV's, refrigerators, and thermostats...), etc. But, Purism (Company) is making computers and phones with hardware kill switches for the microphones and radios. I wish everyone did that. It seemed crazy that the Blackphone doesn't have such switches. 173.228.123.166 (talk) 09:17, 3 March 2019 (UTC)[reply]

Also, even with the microphone out of the way, the gyro accelerometers in phones can be used as microphones.[1] 173.228.123.166 (talk) 09:19, 3 March 2019 (UTC)[reply]