Recently I have been processing my files using a particular sequence of effects in the Master Section.
Today I tried placing the first effect in the Montage Output section, so that it gets saved with the montage with no fuss. Unfortunately the output from the effect is now entirely different (and I cannot immediately analyse what the difference is). This behaviour is the same in 9.1 and 9.5.
The situation is as follows:
I have an Ambisonic A-format set of channels placed in a 4-channel montage on four tracks, the four signals being routed to Lf, Rf, Ls, Rs in order. To convert this to Ambisonic B-format (which is also four channels) I use a special 4-in, 4-out VST which also applies microphone calibrations: VVEncode. This may be followed by additional processing, such as Peak Master. I then place a decoder in the playback processing slot which converts the B-format into signals matching my loudspeaker layout (normally four speakers in a square).
This all works fine until I move VVEncode to the montage output. The effect then is as if the wrong A-format signals are being sent to the plugin inputs; but without generating a series of artificial test signals it is virtually impossible for me to add any precision to that description.