How would one determine if it is not buffering and compressing data client-side for later transmission during "firmware" updates?
Additionally, who has setup an automated testing framework for such things after each firmware upgrade?
How many firmware upgrades have there been for the Echo?
Also, how do we know that your Echo and my Echo are running the same firmware, and will always run the same firmware version?
Yeah, it gets harder when you need to be sure.
>How would one determine if it is not buffering and compressing data client-side for later transmission during "firmware" updates?
AFAIK you can root the device pretty easily, so you should be at least able to verify that the main OS of the device isn't doing this.
>Also, how do we know that your Echo and my Echo are running the same firmware, and will always run the same firmware version?
Boot them both from a read only SD card.
And if it doesn't, you still don't know. So why even bother? Why not simply throw it and anyone peddling it out of the window? That's making sure rather than derping about.
If you have access to the main OS it's also relatively easy to verify that the secretly recorded audio data isn't being uploaded anywhere, unless these devices have some secret radio equipment in them.
Yeah, but this is entirely ridiculous. It's trivial for anyone with access to the device to verify that it most likely doesn't do that.