I have the same problem as dkap - my R50 seems to be giving out with the same symptoms he describes.

I do like the R50 and bought a new MX-450 to replace it. Here's a goofy question: do you think I can put the 450 in learning mode and teach it from my existing R50? Do you think it can learn the macros I have in the R50? (I don't have very many so that's not a show-stopper.)

Thanks!