Logic Pro 9 Nasty Bug: Recorded midi is Playing back the wrong software instrument


New Member
I am running a clean SL install and experiencing some serious bugs in relation to creating software instruments and recording midi with them in Logic. I only noticed the issues this week ironically hours prior to installing the 9.1.1 update. I installed the update hoping it would fix it but no luck.

Basically it seems like an environment related issue:

I create a software instrument and assign it to a Kontakt 4/Omnisphere, instance and assign it to midi channel 1 and then add another midi channel of that same instrument (say channel 2...now its a multi-timbral instrument), and I can play and hear the instrument as expected but the VU meter for that new channel is not moving, it is frozen (if there was a sustained sound being triggered from channel 1). The stereo out and the plugin itself recognize the signal passing through.

Now I can make the Instrument channel strip for midi channel 2 move again as expected by first assigning its output to no output and then back to stereo output.

The above is strange but the worse issue is that on some of my songs (songs with a lot of instruments) when I play and record midi on a track for, say Instrument 30 on any midi channel (1, 2, 3, etc.) it seems to record fine. But it plays back some other instrument in my arrangement instead on playback. If I drag over the midi I hear the instrument I played. However on playback it plays something else. I am not clear on what exactly it is doing as it appears to be random.

The video at the link below shows the issue.

It thought it may be related to the size of my projects but even on new "default empty" projects I am getting strange channel strip behavior in which the VU meter wont show any activity until I "reset" it to no output and back to Stereo Output.

Someone posted about a bug that seems somehow related to my experience with midi and incorrect track assignment and he posted a video here (however he says 9.1.1 fixed his issue). I havent been so lucky.


I've been a logic user since 3.5 and I've never seen a bug like this so I am really worried. I'm at a complete standstill. I am dealing with apple on this as well and I will post my findings but if anyone can suggest any workarounds or suggestions (maybe its a UTM bug, reset pref's, etc). Maybe someone can suggest a good method to clean up an existing project.

Any help is much appreciated.