Security → Router reset every few months-do I have a network stalker?

Every few months my router (second one doing this now) will not be working in the AM. When I check, the SSID I had set for it is then "out of range" but the default SSID shows up. At one point my SSID was out of range and some other network I had never seen before was showing up in scans as MIFI-LIBERATE, once this was what my SSID had been renamed to. I end up having to connect by wire to the router and reset everything on the damn thing. Why does this keep happening? Am I being hacked or is this preset in the router to change the password regularly? Also, my network security key is always fairly hard to hack, as I use a combination of jumbled words, numbers and characters. Any suggestions would be great!

Is WPS enabled or disabled?

Is your firmware revision out of date?

I just restored to factory defaults and reset the SAID and key. While in there I disabled WAS. Firmware is current.

Maybe its a firmware bug?

Has any older firmware ever been installed on this router, or is the firmware on it now the only one available?

If yes [an older firmware was installed], has that older firmware ever experienced this?
If no, how long have you had this router?

What is the make and model of the router?
Is it configured to automatically update its firmware?
Do you have frequent power glitches or outages? (e.g. is it plugged to the same circuit as the refrigerator or microwave, for example)

We have never seen any router which requires you to update your password regularly. The only thing that we can think of is that your router might be faulty. There must be something triggers it to reset itself. What brand of wireless router is it? When it resets itself, does your LAN IP change to default factory setting? If it is, it will be most likey ROM issue on your router. What brand of wireless router is it?

The old Linksys WRT54G V5 routers would regularly reset everything whenever there was a power failure. They should have been recalled because it was extremely dangerous, leaving the network wide open when it happened.