Why do I sometimes log in twice (instead of once)?
I had the same issue due to some mixup of keyrings.
Go to System / Preferences / Passwords and Encryption Keys.
I had two keyrings there, one called "login" with no keys in it, and another called "default" with several keys, for example the password for my wifi.
- Copy the passwords of all the keys in the "default" keyring (for backup)
- Delete the default keyring
- Logout
- Login, and re-enter passwords when asked, for example for your wifi, etc
From this point on your keys and passwords will be stored in the "login" keyring. This keyring is unlocked when you login to Ubuntu, so you only have to enter your password once.
Try removing Plymouth and the restart. And please tell if the problem is resolved or not.
You can refer this link which states that if your password contains number "2" then gnome restarts. Also please tell me if you are using gnome along with Ubuntu .
http://ubuntuforums.org/showthread.php?t=1417140