I am hoping this is a basic problem that hopefully someone out there can help me with.

When I go into google from my Kindle Fire and type something to search for, whatever I type it literally replaces the last character I typed with the current character.
So for instance if I type 'News' then the Kindle would do the following :-

I type the 'N', the 'N' appears on screen.
I type the 'E', the previous 'N' disappears and is replaced by the character 'E'
I type the 'W', the previous 'E' disappears and is replaced by the character 'W'
I type the 'S', the previous 'W' disappears and is replaced by the character 'S'.

So at the end I have literally got the letter 'S' in my search criteria.

It does this on google, yahoo and a few others, but doesn't do it when I type a web address into the browser.

I have noticed each letter as I key it in is underlinded, so it is like I have gone into replace mode rather than Insert mode, but I don't know how to get out of this mode.
If I tab back to the google search box and tab to the right of the character I have keyed then that character will stick but then the very next character I key I am back to square one and have the same problem.

It's driving me nuts !

Any thoughts anyone ?