I have been using the K1,K1 Max and K2 Plus and all 3 have been corrupting my USB and SD car5ds. After inserting into said machines and then connecting back to the PC the PC reports that the USB has errors and needs to be repaired. At first i ignored it then i had to start repairing as it was doing strange things to my PC. Eventually it became corrupted to the point that i couldn’t even format it.
Today i sorted it.
The standard File Allocation Table is FAT 32, which is recommended. Well if you have my issues then format your USB Drives and SD cards to exFAT 32.
Fixed.
Hope this helps.