Disklavier

I have been looking for an answer for a bit.  I believe what I want to 
do is not possible, but thought I would double check here as everyone 
has been so knowledgeable and helpful with my last question

With a disklavier including the old control wagon dkw10 is there a 
program that can scale velocity during playback from a PC.

When I play songs from the disk drive I can use the volume controls of 
the disklavier, but when I play via Midi these buttons are disabled.  
So I am wondering if there is playback software that can in real time 
scale the velocity so that I have volume control?

Thanks