I have the same tv & can scan you a copy of the manual. I've had a quick look and can't see any info on factory defaults in it - but may be of some help?
I'm having problems with mine - sound but no picture and it seems like I might have to replace an inverter board.
Pls send email to email address and I'll reply with scanned manual.
helen.burgess@hotmail.co.uk
March 2008