I'm using Asylum Omni 4.4.3. Yesterday I tried to copu a big file (1,2 Gb) from external SD card (sdcard1) to internal SD card (sdcard0) but at 800Mb the copy stopped. I restarted the phone and tryied with small data and found that, if the data is more than 100Mb, it's easy that the copy stops and the phone have to be reboooted because it remains stuck.
If I try to use the internal SD for backup using TWRP, I'm able to save 1,5Gb of data without problems.
Instead the copy from sdcard0 to sdcard1 is working flawlessly.
I know that in KitKat there were many SD card issues.
But is it possible that 2 different sdcard on the same device have different behaviour ?