Disklavier

I have the DSR1 connected to my MX100 disklavier.  This week in recording
students, I noticed on playback that sometimes the pedal was recorded and
sometimes not.  I looked in the manual under troubleshooting and there was
nothing about pedals not being recorded.

I was just about to call a technician when I had an idea.  I turned the
piano on first and set the midi function to keyboard out, then turned on the
DSR1.  The last few days, the pedal is always being recorded.   The manual
says nothing about having to turn on the piano first.   Has anyone else had
this experience?   Does anyone know why the piano would have to be turned on
first?
I know that on my computer, the scanner has to be turned on before the
computer, otherwise the computer does not read that the scanner has been
turned on.  I wonder if this would be the same with the DSR1?
Terri Ring