Caravan mould issues

Hi,

I have recently been in our Sterling Europa 2004 since the winter and lots of the panels in the cupboards have gone mouldy, particuarly in the kitchen area.  All the pots look clean and the ceiling.  I have had two older caravans previous to this where I have not had the same problem. Whats the best way to avoid this problem?  I am concerned that a dehumidifier will shrink the fittings which are already shrinking). Does anyone else have a similar problem? Last year when servicing the Caravan we were told that there were no damp issues.