I was very pleased when I first took it apart, washed the rubber and successfully re-assembled it. The remote worked as well as it had when it was new. However, after a few months it was working poorly again.
I have taken it apart (surely it should have been easier the second time?) cleaned everything I could see, and tried the eraser as well. I've now put it back together (twice - as the first time I left out the metal wheel) and am hoping that this time it keeps going for longer, otherwise I may have to resort to buying a replacement.