Thanks George,
Yes I think that pretty much all the arrangers adopt the channel 5/4 combination as the default on the keyboards.It seems to be the adopted defacto standard now.

I have seen a quite few SMF's (from other commercially licenced suppliers) that are all following this.

Strictly speaking, I probably shouldn't say it's part of the spec, but its just as easy to say it that way, rather than enter into long explanations which can make it a lot more confusing, particularly for beginners.

Dennis