I noticed this error when executing ifconfig just after turning VStarCam H6837WI on:
# ifconfig eth0 192.168.1.126 up ifconfig: SIOCSIFFLAGS: Invalid argument #
I didn’t investigate what is the root cause of this error, but I noticed if I execute /mnt/system/bin/encoder and reboot the board next it it will work.
Then I suspect there is some ethernet Micrel KSZ8851 PHY initialization done by encoder application.