"alan_m" wrote:

The gap between the floor and the kitchen unit base seems to go to zero at
the point of the dodgy board. Could the kitchen unit kick board be too
tight at the point where the floor rises slightly and is levering down the
laminate plank on one side of an underlying joist - and causing it to rise
the other side of the joist? Perhaps remove the kick board to see if the
floor naturally recovers and if it does just shave a bit from the kick
board at the appropriate point.

Thanks for that. I've now removed the kick board in the photo, and another
nearby one at 90 degrees to it (the kitchen units being in an L shape) but
it's made no difference. I'm beginning to suspect that there might be a
problem with the underlying floorboard(s) which if so will be a real pain.
none of the laminate in this area seems to be lying properly flat and there
are signs that another board is going the same way as the damaged one.

I hope it doesn't come to removing the kitchen units.