I have the above device and am wanting to flash it with updated firmware from tanix. However when I try to install update via tf card or using the usb burning rom I keep getting an error and unable to flash. I keep getting an error E:failed to mount /dev/block/mmcblk1 on /sdcard by read-only (invalid argument), has anyone come across this and know how to fix it? I tried to mount SD and it confirms it mounted but when i click to update again I get the same error