I'm missing this but everything else matches yours.
/dev/mmcblk0p3 1.6G 470.4M 1.1G 30% /config
That's the writeable /config partition
So yeah without that mounted, it can't save any settings that survive a power off.
The command to see the SD card setup is:
fdisk -lThis will explain what's wrong.
In should be:
Disk /dev/mmcblk0: 7909 MB, 7909408768 bytes
255 heads, 63 sectors/track, 961 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/mmcblk0p1 * 1 9 72261 c Win95 FAT32 (LBA)
/dev/mmcblk0p2 11 19 72292+ c Win95 FAT32 (LBA)
/dev/mmcblk0p3 20 239 1767150 83 Linux
If it's not the same, then it will needs correcting.
If it is the same then that means the /config (/dev/mmcblk0p3) partition is corrupt and needs fixing with fsck or reformatting.