Yamaha DTXpress/DTXplorer/DTXtreme

I have a DTXpress 3 special and I have been checking the settings and 
I have noticed that I don't seem able to get a splash sound on the RHH 
130 Hi-Hats! I get the first five OK - Open,Open Edge,Close,Close Edge 
and Foot Close but no splash? I can get the splash sound if I set it 
to splash on foot close, but I thought that I should be able to get 
all six sounds from the RHH130?! Anyone got any ideas as to what I am 
doing wrong? Many Thanks.