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Comment by ggambetta | Hacker News Reader

Would be easier to do a hex search on the binaries, find the device id of the old mic, and patch in the device id of the new mic. I'd be surprised if they had bothered to obfuscate the id in any way.

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Now you mention it I feel like I overlooked the obvious solution.

Hahaha :) To each his own, I guess. I would have never thought of anything involving a soldering iron!

Good excuse to break out the soldering iron.

permanently modifying the hardware is the more portable solution. it will always work with unmodified software i.e. at a colleague's location. i presume your wife works with others that use the same platform.

>permanently modifying the hardware is the more portable solution. it will always work with unmodified software i.e. at a colleague's location.

No, as OP mentioned, the software was compiled to match the device ID of the mic it was shipped with. So it would only work with versions of the software that were the same as OP's.

I think you misinterpreted. It's the USB device ID, which contains a unique to the model ID and the vendor ID, so any software would work with any device if it has the same model ID. There isn't a such thing (at least not standardized) as a unique device ID.

I think you misinterpreted, because you repeated what I said.

>So it would only work with versions of the software that were the same as OP's

What he's saying is that there might be V1, 2 and 3 of the microphone in question. The software is tied to a single version of that microphone so any microphone of the same version is indistinguishable to the software.

>the software was compiled to match the device ID of the mic it was shipped with.

Since there isn't a "device ID", only a "Model ID", there isn't a new compiled version for everything being shipped. There's maybe 3 or 4 versions of the software total and there's probably one version that's more prolific than the others.

He may not have been able to buy one of those USB Microphones off of Amazon that had the same VID and PID but the old model that he repaired is one of the few versions that the manufacturer used so there's a pretty decent chance that the fixed one will work as is with another computer with the software on it.

okay.

Although, did you get any of the other legitimate mic's to work? Its possible that the device has a serial number burred in one of the USB descriptors and is using the mic like a hardware dongle (or worse a robust DRM scheme).

But, if you hack the binary, its probably worthwhile to spend a little extra time and completely remove the id check. That way you can use any random mic you find.

Alternatively, would be fun to get the OS to lie about the USB device ID. This would definitely be possible on Linux (probably with a kernel module, but perhaps you'd have to modify the USB core) but no idea how flexible Windows is on this kind of thing..

Should be possible with DLL injection or function hooking since I would guess they just check the USB id and then use the normal mic access functions so you would only have to intercept 1 or 2 calls.

On linux LD_PRELOAD should be enough.

I don't know whether it still works in Windows 10, but you may be able to tweak an .inf file to map the driver to the vendor ID/product ID combination (https://msdn.microsoft.com/en-us/library/windows/hardware/ff...)

That also may require playing with settings that require drivers to be signed (http://www.alphr.com/blogs/2012/08/06/getting-older-drivers-...)

I'm wondering if that's "more illegal" than fixing the hardware component (which is silly because changing the ID can be simpler). In hardware you can just say you've replaced a broken part even if it's 99% of the hardware, right?

Won't be so easy if they obfuscate/encrypt the binaries.

Could do it live, but it's more annoying.

The same way we used to crack old games. That is how Mech Warrior on the PC fell.

They're only 16 bits though so you will get a lot of false positives.

I thought that was what he was going to do. Hopefully they didn't add too many protections on the software side.

would you simply change the part of the hex in the binary that references the mic id? I was not aware i could modify the hex directly .

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