Problem with flex melting on Morphy Richards Steam Generator Iron?

I am on my third Morphy Richards steam geneator iron. After 6 months or so the cover on the flex melts and seperates away from the actual iron due to built up of heat from the steam (I guess) The flex seems to get very hot. I would use the iron once or twice a week for possibly half an hour up to 2 hours. Morphy Richards have said there is no fault and just to bring it back to the retails who will replace it. Has any one experienced the same thing?