On the PSR2000 I owned, the toggle buttons were of a 'rocker design', with each button controling both volume increase & volume decrease, depending on which end (bottom or top) of the button you push. Tyros & Tyros2 on the other hand, includes a separate dedicated button to control volume increase & volume decrease. Not certain if this difference (improvement?) in design affects the life/durability of this feature function or not, but like I said before, I've never encountered a failure or problem with this on Tyros1, and don't expect a problem with Tryos2 either.

Another Important Note I almost forget to mention: I now remember having experienced problems with the physical sliders on my Roland RA800 arranger. Every so often while operating the sliders, a scratchy electronic noise would sound thru my pa speakers/headphones. I was advised by Roland that a piece of debris (dust/grit) may have gotten into one of the sliders assemblies. I don't experience the annoying noise problem resulting from worn/dirty variable volume sliders parts on Tyros2, because the physical moving slider parts have been eliminated.

Scott