Some happy news tonight (at least it's night for me): Rick Dastin and Francis Tse rang up a few minutes ago. Long story short:

• It was a bug indeed,
• the issue indeed affects all compression modes across a whole lot of devices, all are able to mangle numbers,
• most important, they found the bug,
• a patch is being developed,
• and they want me to test it using my originals (this is an honor, I appreciate this).

Here is their press statement. I am glad not to go down in history as the guy too dumb to read the manual.