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Everdrive maker Krikzz has highlighted an issue with newer variants of Analogue's popular Pocket handheld which means Everdrive flash carts do not function properly.
Flagging a forum post by Analogue Pocket owner elfricko, Krikzz notes that "when the system writes to a file, it reads the sector containing the directory information, applies the required modifications, and writes the sector back. However, in the new [Analogue Pocket], some bits become corrupted for an unknown reason, resulting in damaged file system sectors."
According to Krikzz, this appears to be a hardware-related issue. "With [the] same firmware version [on the] old [Analogue Pocket] it works well, but [Analogue Pocket] from the new batch does not work."
Analogue has apparently been contacted regarding the problem and has stated that it does not provide customer support for third-party devices.
That's a fair comment, given that Analogue cannot possibly support every single accessory or device designed to work with the formats covered by the Pocket (that includes Game Boy, GBA, NGPC, PC Engine, Lynx and Game Gear), but companies operating in this space have usually been quite accommodating when it comes to sorting out these issues.
Still, as some have noted, there's a chance that the issue could be more complex:
It would seem that some kind of issue with the newer Pockets is to blame – so, if you're looking to buy one and intend to use a flash cart, you might want to wait and see what happens.