I had a very similar problem, The lervia comes with a good guarantee I contacted Lidl and they sent me a proof of purchase letter which was forwaded onto DES Ltd their authorised engineers. They did not want the shredder back simple replaced the item. Note this can take up to 28 days but the item is replaced free of charge and comes with a 3 year gaurantee. DES Ltd contact no if you still have your reciept is 0870 7876177 if not contact Lidl direct.
Hope this helps
John N Peterborough, March 2009