I definitely started to notice it with the Forma, and I just chalked it up to Nickel being a tad heavy-handed about handling /mnt/onboard during USBMS sessions, and/or the fsck version they ship being stupid about clearing the dirty bit.
I never actually ever encountered a real FS corruption, and a proper, recent fsck run basically only ever clears the dirty bit, so I've just stopped wondering about it ;p.
EDIT: A quick glance at my dmesg shows that, yep, also seeing it on the H2O. Except in that case I *may* have had something to do with it, because I *did* actually unmount onboard like a savage a couple times ;p.
Code:
[73769.000316] FAT-fs (sde): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
Code:
fsck.vfat /dev/sde
fsck.fat 4.1 (2017-01-24)
0x41: Dirty bit is set. Fs was not properly unmounted and some data may be corrupt.
1) Remove dirty bit
2) No action
? 1
Perform changes ? (y/n) y
/dev/sde: 15178 files, 485455/829227 clusters