Actually the current OS is 2.8 and there is another new one coming soon. I apologize that I haven't updated the OS link on my site. The 2.8 OS contains the KB3 mode (hammond organ emulation mode), Live Mode (allows external signals to be processed throught the synth using the sample in) and other enhancements. There is a new OS coming soon. Check out the NAMM highlights in the NEW section of the K2500 Zone.(posted 9195 days ago)-Mike