Quoting Doug Goldstein <cardoe(a)gentoo.org>:
FWIW, if someone needs a device to test a potential patch with just
take any rooted Android phone. e.g. an HTC at the HBOOT menu presents
itself as a different product ID than when the phone is normally
booted. You can also do this with an iPhone, just hold down the power
and the home button to boot it into a "recovery" mode where it'll have
a different product ID than normal.
Okay, thanks; so now I know that it's not just badly designed hardware
that may do this. My device, however, is not a smart-phone or some
other consumer device: it's a scanner with a rotating drum on which to
mount flexible, reusable photographic plates from an X-ray machine.
It's rather expensive too. Of course, it only works with a Windows
application. Can you imagine a legitimate reason why a machine like
this might keep flipping its product ID?
Cheers,
Jaap