the FX2 has been out for nearly a decade now, they're probably scavenged or NOS.
It's even worse than that. Saleae tells an interesting story about involuntarily receiving remarked old-rev parts which don't meet spec:
You can be sure the chinese clones are full of them.
Bingo. You can buy FX2 chips with the old mask stepping in china for about 2$.... They contain some silicon bugs and they run hot , but for what they do with em its just fine.
I happen to know the guys from Saleae. I went to one of their open houses. They have awhole bag with all the different clones out there. The saleae has additional protection diodes and resisotrs and some other stuff that the cheapos don't have. Besides the biggest effort is in the software.
The software can actually detect fakes and they contemplated having it ping home when this was found, but ultimately they didn't do it. They can also disable a clone but elected not to do this. The makers of the Logic and USBEE do disable the clone if they find one. The trap lies i theused eeprom. Saleae uses a particular eeprom that holds the vid pid and bootcode for the 8051. The chinese clones use a different onr. They can read the eeprom signature and retrieve the eeprom maker and model.
Their eepro. Is larger than in the clones because they left room for future expansion. The chines,being cheap, use a smaller one.
You can get off alibaba boxes that do everything. Using two or 3 jumpers you switch them from being a Saleae to a USBEE to a byteblaster to a xilinx cable and back. All the jumpers do is connect a chip select pin . The boxes simply have 4 eeproms in them, each with the 'stolen' vid pid pair.
The hardware is cheap but the software is pricey because of the man hours in maintenance and updates. That is what you pay for. The chines have no maintenance or development. All you get is a weak xerox of the hardware and you go use it with the software you grab from the web. Pure piracy...