In the meantime have you got a filter in your machine which you have access to, to take out and clean and if you haven't yet called someone out try and get dh to move the washing machine so you can see if the grey tube with the crook init is clean and the pipe it goes into is ok.
Also you might want to try a pack of soda crystals on a hot hot wash (may be the whole pack or just half)
But it does sound like its the machine