The "one touch" function of certain buttons must be related to memory because the entire low line of psr gear seems to act that way. Maybe it has to do with the fact that so many buttons become editable with the data wheel after they are selected.
For example ..... it would be a disaster if the last thing you touched was the tempo control and wanted to change key later on. If the button "last pushed" was still active....an intentional tempo change would result in a disasterous key change.
Who knows......
All I know is that this 2100 is making me nuts. Key feel, key size and many other things. I applaude you guys with simple needs. My taste just needs a better constructed keyboard with all the bells and whistles that the psr line packs into the smaller units.
It's just a question of time before SOMEONE actually makes what I need. sigh .......