Disklavier

Hi all,
 
I recently had a recording session that used a Disklavier.  We needed 
to record the actual piano sounds as well as get the corresponding 
MIDI.  For the most part, it worked well.  Our resulting audio files 
are great, and the corresponding MIDI almost always matches 
perfectly.  There were a few exceptions though.  In a few of the 
files, the MIDI would cut out for almost exactly 30 seconds, then 
after that silence, it would return, still in sync with the audio.
 
There are a few possible explanations for this.  It's certainly 
possible that the MIDI interface going into the computer was faulty 
in some way (audio and MIDI both recorded into Reaper).  Me feeling 
though is that it was probably something getting stuck on the 
Disklavier's end.  The exact devices were Disklavier II, and the 
controller that spit out the MIDI was a DKC100R.
 
Has anyone else had similar issues?  Any suggestions for how to fix 
this?  We're planning on going back to the same studio, with the same 
setup, in a few days, so we were hoping to have something new to try.
 
I did try searching previous posts for "lost MIDI", but wasn't able 
to find anything pertinent.

Any help would be greatly appreciated.  Thanks very much!