Korg Poly800/EX800 Users

I am trying to load original sound bank into EX800.
I have the Audio Cassette wave file from Files section as well 
as several Sysex banks from File section.
None seem to work.
The cassette wave file never passes the verify test.....I tried 
all combinations of Line Out, Headphone out, etc.....all fail and 
all different levels.
I use Sonar....my midi is working fine....I can play sounds and change 
patches from Sonar....but when I send sysEx files nothing happens.
Does anyone have any advice on how to get either to work.

Thanks.
jeff