I know 
The thing is that you have again, twice defined some functions.
Let’s check the mixer page mOnActivate.
You have at one point:
Mixer.mOnActivate = function (activeDevice) {
midiOutput.sendMidi(activeDevice, [0x90,44,127]);
}
This is OK.
But then later on, you have:
Mixer.mOnActivate = function() {
for(var i = 0; i < 8; ++i) {
makeEncoderPanFeedback(pushEncoders[i],0x30+i)
}
}
Again, the compiler can be confused. So, you should really merge your commands in one function and remove the other. I think you should keep the first one.
Now, the second one is not something I like. I’m pretty sure you’ve copied/pasted this to some extent, but it’s not OK for the compiler. Totally delete the second code segment mentioned above. Concerning feedback for the encoders, you can create a new function that can send the necessary midi messages, based on the currently selected page. I can help you with this too, once you explain to me a bit, why you need these different feedback values.
For example, I see in the mixer page you want a pan (?) feedback and I see this:
newValue=newValue*10.99+17;
Then, in the EQ page, I see a makeEncoderSpreadFeedback function, where you have this:
newValue=newValue*5.99+49;
I understand that you somehow try to normalize values here, but I really want more details.