I have a project [A] set up as a multioutput instance in Logic. I set this up from scratch with four sample instruments. It works fine. The instruments are two violins, harpsichord and viola da gamba, in other words a standard trio sonata lineup. I've saved that as a multi.
I wanted to replace the violins with a different solo violin sample instrument, so I saved project A using Save As, giving it a different title. Then I replaced the two violins with two new sample violin instances. I checked the routing of the outputs to Logic, and it seems on the surface to be ok, except it's not because the violins don't play at all. The harpsichord and the gamba tracks play when I have the violins unmuted or soloed.
The midi channels assigned to the tracks in Logic correspond to the channels in the vi instances in the Kontakt multirack.
So obviously I have routed something wrongly, but I don't know how to fix it!