Yes, the plastic ones. I've had the steamer for about 8 months and use it two or three times per week. It's been OK until recently, but now, for some reason, they won't clean properly. It could be due to the hard water I have here. Looks like I'll have to try an abrasive of some kind as I've tried standard hand and dishwasher cleaning, as well as white vinegar.
I am using the specialist formula you can buy for high-spec plastic kitchen sinks (mine is white......). You should be able to find a proprietary one at most large branches of Focus, B&Q etc
Leaning towards cleaning. Am the Queen of my own castle.