I just asked sandisk.
Most of my extreme pro cards are newer models: SDSDXXY-128G
Those Sandisk Model-Numbers are cards that were only available in Japan, as the last digits of the model number are region codes.
And they arent available today anymore. So basically its not possible to get a sandisk cards thats on the list today.
But the new Lexar I just bought is LSD128CB1667, which is on the list and it fails.
The only one that passes is the new Extreme Pro 32 gb - which is not on the list.
So maybe it has problems with SDXC - Cards.
I already ordered a Kingston-Card from the list - which is only available from amazon us.
I have never had problems with my cards on many differend cameras and audio recorders.
Its very strange that the zoom could be so picky about cards.
That would mean the recorder is useless, when all cards from the list arent available anymore?
This cannnot be possible, or they just built in a VERY cheap SD card reader..
A brand new Sandisk Extreme pro 32gb passed the test multiple times, then I got a brand new Sandisk Extreme Pro 64 gb and it immediately fails.
It seems like the F6 has problems with sdxc cards, while sdhc passes.
Unfortunately 32 gb will not get me through the day. Its 7 hours with all six channels activated.
So I will have to change cards when I keep the recorder running to sync later in post.
Thats very strange...
A lot of users reported they have absolutely no problems with larger SD extreme pro cards.
I just noticed something. Earlier you said "hope it's the same model" about the latest card you purchased. There is no need to hope; the part numbers should be clearly stated by your vendor. Please see my earlier post where I mentioned that unless you are using the same exact part numbers from those on the tested lists, then those cards are different internally (despite the same external branding). The branding of "Extreme Pro", "Ultra", etc. doesn't mean anything for this application. In this case, the only 64 GB SanDisk on the F8n Pro list (the newest Zoom tested list available) is SDSDUN4-064G-GN6IN.
I suspect that you may have not yet tried any cards that are on any of Zoom's approved lists. I know you have bought several cards already, but you need to try one of those cards first before thinking the new production run of F6 all have hardware problems. You may be correct, but let's minimize the variables.