didn't have any problems with my 66st, a few weeks back i thought i 'upgraded' to 66i, my old 16GB card that worked fine in the st didn't work in the i at all.
went out and bought a 32gb card, format it with MSDOS, it shows up in file explorer, it shows up in basecamp when plugged into the unit, i went ahead and sent a bunch of birdseye stuff to the sd card through basecamp, checked the sd card and i see all the files on there, go on my hike today, power up the unit and bam, nothing on there
i see some 7 month old threads with the same exact issue, is this a firmware issue, is this a unit issue? considering i didn't have the issue with 66st makes me think it's either a unit issue or specific firmware issue?