Thanks for all of the replies. Looks like it was the LCD rubber connector playing up again. This time I cleaned it with isopropyl alcohol rather than contact cleaner and now its better than ever
But may need a better fix in the future if it plays up again. Saw one dude on youtube using a thin layer of conductive grease.
As for a lifetime warranty I certainly don't have the original receipt nor am I the original owner of this meter.
cheers
david