I must be missing something in this thread, because I am having a VERY similar problem, but the above steps didn't help. I am on Sibelius 5.2.5 as well, and I am trying to get my winds playing correctly. I have a Flute set up on MIDI channel 1 in VE, as well as Flute 2, Oboe 1 & 2, and Bb Clarinet 1 & 2, one channel per instrument in that order (as well as other instruments which are disabled right now). I cannot for the LIFE of me figure out how to get Sibelius to OBEY my setting in the mixer that supposedly puts the Clarinet on channel 5. Instead, whenever I test the Clarinet 1 in Sibelius, whether in the mixer or in the score, it ALWAYS plays it through to MIDI channel 1 (flute) instead. If I switch the channels around, it generally plays the correct channel, except that 5 always goes through to 1.
This is driving me up the wall. I checked my manual sound set configuration -- everything is the way it should be. I also removed the '.2' instruments as stated above, and instead used Flute 1 for both flutes, Oboe 1 for both oboes, and Clarinet 1 for both clarinets. Once I did that, I saved it, did a once-over on everything to make sure everything is set up correctly, and NOW the Clarinet on channel 5 plays through to the flute on channel 2! Not only that, but changing the channels in the mixer causes it to output to an unpredictable channel number. It's like a bunch of criss-crossed wires.
Every now and then I overlook some dumb little setting, but this is ridiculous. What one earth is going on? Any other ideas?
Thanks,
Scott