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Comment by WalterBright | Hacker News Reader

Alexa should come with a physical switch on the top of it to turn the mike on/off. Not a software switch. It should also have an LED that glows when the mike is on.

If it had that, I'd buy one.

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I've always asked for hardware safeguards, and I wish more people would demand them. I want the camera & microphone on my laptops & desktops to get their electrical power THROUGH an in-series LED, so it simply doesn't matter how the decision to start watching/listening is made, the device can't be powered on without making the LED glow. No other source of power except thru the LED.

There would also be a hardware switch in the same series. Turn it off, and no power can reach the device, no matter what the software decides. Manufacturers could easily make the circuit testable, so if you tell the machine to start using its camera, it could test the circuit and tell you that the switch appeared to be turned off and show you a little diagram to help you find the switch in case you accidentally switched it off and didn't even know it was there.

Most manufacturers who claimed to have this feature would do it correctly, because they would have to assume that somebody would disassemble a unit and damage their reputations if they faked it.

> THROUGH an in-series LED

That's a pain electronically since the brightness of the LED would vary depending on the current drawn by the camera and/or microphone. In order to not blow the LED, the circuit may have to be set such that the LED wouldn't be bright enough to notice reliably when the camera is in a lower power (but still functioning) mode.

You could easily get what you actually want by putting an LED in parallel with the power supply to the camera and/or microphone though. Then the LED would maintain a fixed brightness but wouldn't be able to be switched off unless the power to the camera/microphone is cut.

Separately, it's possible to have unpowered microphones. I suspect laptop microphones are of the unpowered type (and amplified elsewhere). It's still quite possible to have a circuit which is hardwired to be incapable of passing the microphone signal without lighting an LED.

I'm just saying that your "in series" demand is unrealistic, and instead you should prescribe what you actually want rather than specifying an electronic circuit that can't necessarily achieve it.

The original Amazon Echo has a physical switch when you mute it. A friend of a friend worked on that and he is a giant security nerd so he made sure a physical switch is designed in.

I just unplug it, and when I want to listen to music plug it in, problem solved!

Putting it on a bus strip with a power switch is definitely Plan B, but it's inconvenient.

My bluray player spends a lot of time fruitlessly searching for an internet connection when I put a bluray in it, and eventually it gives up and just plays the disk. I see no reason to connect it to the internet so it can spy on me.

Don't Blu-ray players have to get updates sometimes or certain discs won't play?

Technically yes, but due to how first generation Bluray players will never have updates to their DRM keysets, there have been extremely few discs that chose to employ new keys.

This may become a thing for 4k Blurays (since all 4k Bluray players are long since compliant with the over-the-internet key updating mechanism), but unlikely because most manufacturers still refuse to update anything after warranty ends.

Ergo, the Bluray industry doesn't want to tie themselves to a model where people have to buy new players every 3 years: people will just stop buying discs instead.

The other OTHER side of this is: the disc is dead. Most people own very few discs, only of their absolute favorite movies they want in a high quality copy or for the few people who are bothering with 4k content (since most people still do not have enough internet to stream it); so why rock the boat, just let the format play itself out.

The disc may be dead, but most of the movies I want to watch are available from Netflix only with their disc service. I also borrow discs from the library.

But you're right that I'll only buy a disc for a special movie.

Its long boot-time makes this inconvenient, unfortunately.

The dot I was developing for today has a mute button and the LEDs show red when it's on. Pretty sure I've read that the switch disconnects the mic. Is this comment sarcastic?

Interesting reading:

https://iot.stackexchange.com/questions/2382/is-the-amazon-e...

Would you still trust that it's off when it says that it's off?

If you could open the case and verify that the switch does what it's supposed to do, why not?

Yup. That's the point of a physical switch.

Since the board schematic is presumably proprietary, and the board could be multi-layered, you'd have to do some fairly destructive investigating in order to confirm that the switch is actually doing what it says it is doing.

Not as long as it cuts the wire that breaks all connections between board and the microphone(s) (and board is somehow audited to not contain any extra microphones or otherwise sound-sensitive components).

<tinfoil hat on>But this is only as long as you actually can verify or trust that the switch is actually a switch and not a device that pretends to be one. A transparent casing where one can visibly confirm the actuator operation is a good idea.</tinfoil hat off>

The problem with that is that you can turn speaker info a microphone:)

True, but a multi-pole switch can also cut connection to those.

If you want extra tinfoil hattiness, most multilayer ceramic capacitors (the surface mount kind that are everywhere on PCBs) are somewhat microphonic. Condenser microphones, especially electrets are basically just capacitors designed in a special way to maximize this effect.

Interesting! I know about condenser mics, but I thought a typical SMDs are way too small to sense anything useful. Had anyone experimented with this?

They generally are too small to be useful. That's why I called it "tinfoil hatty". Most of the issues with them come from mechanically coupled vibrations in a system (from fans and the like) flexing the whole circuit board, so it's not as big an issue with phones. Also most of the capacitors are power supply decoupling caps, so difficult to sense variations from.

It's mostly just a fiendishly annoying effect in high-sensitivity test equipment.

I figure one of those teardown article/video people would tear it down and confirm.

If Amazon advertised it as a physical switch, and it was not, that is fraud and actionable.

> If Amazon advertised it as a physical switch, and it was not, that is fraud and actionable.

A physical switch is still a technically a physical switch, even if it's not connected to anything. It would come down to how they are describing what it does, and what guarantees they make (or not.) Do they have any, or is this discussion entirely hypothetical?

They need to advertise it as a physical disconnection of the microphone.

The switch doesn't need to be part of the main board --- it could be located next to the mic, so it's trivial for anyone with even the most basic electronics knowledge to see that it does what it says it does.

Well, that's trivial - the 'Echo' functionality is just an AWS service:

http://www.instructables.com/id/How-to-Make-an-Amazon-Echo-W...

On a Raspberry Pi or similar machine, you can hook the logic up to anything; a button, a switch, an infrared remote, whatever.

My echo has a switch, I can press it and it lights up red to indicate its muted.

The entire point of Alexa is to be able to talk to it from wherever you are, so doesn't walking up to it every time defeat the purpose? A regular speaker is cheaper and has much better sound quality.

And yet I still want the choice to lower the Cone of Silence when I want to.

> Alexa should come with a physical switch on the top of it to turn the mike on/off.

Axe should do it.

Can't you just unplug it?

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