Hi Jaro,

I haven't encountered this particular problem but perhaps the troublesome MIDI files have Patch/Bank No's that are incorrect for the KN7000.
I presume the problem occurs for all methods of loading (GM to GM/GM2, GM to NX, etc.).
If you have a suitable sequencer program on your computer you can probably ascertain exactly which Patch/Bank No. combinations are being used in the troublesome files.

Cheers
Len C.