I bought a PA50 a few months ago and it had V1.04 dated 2004. One thing i did notice was how long it took to load the OS (>30 secs). So i updated it to V1.05 dated October 2005 and the first thing i noticed was how quick it loaded the OS, less than 10 secs. It also cured problems of keys not sounding esp. I probably think that problems like that are due to polyphony i.e. how many notes the keyboard can play at any one time. This can depend on how 'full' sounding styles are.
I've had this problem when i used styles converted from Yamaha, Roland and Ketron.
