Please try this workaround:
Post
RE: Legacy v9.2 (LTS) builds for Amlogic S805/S8X2, S905/S912 and all WeTek boxes
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Unfortunately, if a storage device is connected to an external USB (external HDD, flash drive, etc.), it would try to boot from there first.
If you need to ignore startfromext, you need to set this:
(Code, 1 line)
And then reboot. If all goes well, it will no longer try to boot from an exernal device (not even an SD card).
Unfortunately, if a storage device is connected to an external USB (external HDD, flash drive, etc.), it would try to boot from there first.
If you need to ignore startfromext, you need to set this:
(Code, 1 line)
And then reboot. If all goes well, it will no longer try to boot from an exernal device (not even an SD card).

dtech