I have a 6442g-b(ec). I’m using a 8GB stick, it’s formatted to FAT32.
This is what I get from nautilus when I read the usb stick.
The Ruida manual
This system supports such file formats of Udisk as FAT32 and FAT16, but it can identify them when the files are put under the root directory of Udisk. The file name of more than 8 characters will automatically be cut out by the system. The file name that has only English letters and digits will not how when they are copied to the mainboard. The files copied from the mainboard to Udisk will be placed under the root directory of Udisk
Mine seems to work…