Language setting of JVC LT - 17 E31 TV to ...

Hi, I have a telly that thinks it's icelandic or something !
It keeps swapping ENGLISH (my language) for other languages (which is usually sorted by turning off & on again). However, recently, no amount of power down>power up will reset it.
I can't find anything about this problem in the manual & the Menu won't show 'INITIAL SETTINGS' (if I could get to that, I'd be able to correct the problem).
TIA - John.