Some folks suspect that the problem on these is actually trashed Flash chip(s) and not in fact a hardware fault.
In particular the wear leveling seems to break down and result in this fault, if some way could be found to simply zero the entire memory then reload it from scratch the problem would be gone.
I had some success "nuking" 32GB microSDs, so far 3 good out of 3 although they didn't last much more than a month at least it proved the technique is sound and triggers wear leveling of the bad sectors when all else fails.
It was an experimental setup with a 9V gas igniter transformer running at 27V with a series current limiter, feeding into either a 5642 or any old cheap radio valve with a Mg getter such as "made in UK" ones.
My X-ray meter was clicking away merrily so this was full spectrum down to <5KeV.
Its the low energy X-rays that are the most hazardous and needless to say this is not a recommended technique unless you are trying to wipe memory chips on purpose.
YMMV, lead lined everything and preferably two layers of shielding between you and the device with failsafes and suchlike.
Note that your average tube will *not* pick these up it has to be an end window or thin wall Bi cored tube such as the SBM series with no compensation shielding running at >450V and a compensation network to prevent destructive oscillation.