DrLumen
It had a lot of dynamic changes and it appears these are now causing problems in X3. I can hear it is not right but the automated sliders would give a better idea of exactly what is going on and where the problems may lie.
This statement has me wondering if we are all on the same page here.
Are you expecting the sliders to respond to levels in the audio? In other words, when the peak levels increase, the sliders move up?
If so, that's not how it works.
The sliders move only if they have a volume envelope to follow. Most often, you would create this in the track view. If there is no envelope, the sliders remain stationary. They are linked to the volume level you have set in the track view.
The sliders(and volume envelope) do give you a way to control overly active audio tracks.
If I am reading you right, a Spectrum analyzer, such as Voxengo SPAN, might be the tool you are looking for. In X3 Studio, we don't have the cool analyzer built into the Producer ProChannel flyout. Maybe we'll get it in X4(one can hope).
One thing to bear in mind, especially in the context you have given of the project, is that many softsynths tend to run a bit hot. Sometimes, simply turning down the synth output level helps a lot. If you turn on the Waveform Preview in the synth audio track, it will pinpoint any clipping from the synth output.
You can also adjust the velocity of the MIDI feeding the synth, but this may or may not be ideal, because it can affect the tone/timbre of the notes produced by the synth.
Which synth(s) are you using? More specific information may be helpful.