Does this process work for let’s say DRM encrypted music too?
No. These use Widevine DRM.
As you can tell from the security section of the article, it is not exactly impossible to crack, and I'm certain private groups have their own way to get past it.
But if you're just looking for audio, then you can just record your computer's output audio stream.
Open it up!
They put a regular old switch inside a fancy box, but you'll be able to read the part number once you see the actual switch.
Unless you've managed to get a switch made out of superconducting material and you're working inside a liquid helium bath, everything has resistance :)
You'll have a bad time trying to measure such low resistances, so usually you can look at the datasheet for the switch you're using or for a similar switch if you need a ballpark number. You'll see an on-resistance, and a max current (since there will be arcing when you open the switch).
If you do want to measure the low resistance, you'll need dedicated meter with a kelvin connection.
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