This kind of jump usually occurs when there is an expression changing the dynamic.

Are the four horns on separate staves, or are you using layers? Dynamic expressions do not always affect all layers equally, especially if the layers are set to different MIDI channels to run different instrument instances.

I do not know what you mean by "The ARIA's Control panel has the same numbers for all 5 buttons."

Thanks, they're all on Layer 1, each with its own staff, like a regular (not condensed) orchestral score.

My ARIA Player has four tabs/pages on the right side.  They are Mixer, Controls, Effects, and Settings.  On the Controls tab/page of the ARIA Player, the adjustment buttons/knobs are for Porta, Length, Var1, Var2, and ModWhl.  The ModWhl is the only one that changes, but only when the screen is not being looked at.  Adjusting it has no permanent effect, even after hitting File, Save.

I've had some ID theft/fraud issues, and I suspect this is part of the same.  I had a great smooth jazz tune which developed some "problems".  If people think other people should do something other than try to make music, who am I to disagree?

Do I remember something about "either use the ARIA Player mixer OR the Studio View mixer"?  I'm changing the sliders in the ARIA mixer, but they automatically re-set to their previous levels.

Okay, so I've gone through and clicked "Not Sending" on each of the instruments in the Studio View, and that seems to have taken care of it.

And on a Surface Pro, you have to use the Magnifier, to make it easier.

Now I just have to figure out why the Tempo Tool doesn't take on the first attempt...

The Finale Mixer sets basic relative levels for the various instruments. Dynamics do not affect those settings.

The Aria Mixer reflects changes in dynamics through the piece of music and therefore changes levels often.

Yes, but these were dynamic changes NOT programmed by me.

I just found the solution:  I turned off the Human Playback.  It had, for instance, the 1st and 2nd Violins dropping to zero volume where there was no expression for it (or if they were trying to play "piano", why didn't they do that 4 bars earlier where I wrote that in as a dynamic?).

So, yes, it "sets basic relative levels", which is why I purchased the upgrades when I could afford them!  This is simply GREAT software. Of course, because it has so many things built into it, you can tell when someone has been fussing around with it.  Finale wouldn't make stupid software, because (as anyone can tell) they know that what goes around, comes around.

Glad you found the explanation.

Well, it's a start-- I will eventually want to apply Human Playback to the piece, and will need to be able to tweak it, if it continues to act up.

Thanks for the input; it all helps.  I've noticed a trend in the past about putting "too many" expressions in (although it was nothing you wouldn't see in a normal score), but I thought it was because I was using a Surface Pro instead of a "regular" computer.

By the way, I've distributed the instruments among several banks, to ease the gridlock on the 16 channels.  Any thoughts (and this would be for a regular orchestral ensemble-- woodwinds, brass, perc, strings)?  For some reason, I've always been in the dark re: MIDI.

Although I have no firsthand experience on this, the trend seems to indicate that a given note is affected by its surroundings (note placement, dynamics, dynamic changes, tempo and tempo changes, technique instructions, etc) it more than any other factor, evidently.  I'm mentioning that because I think I've seen the exact same problems regardless of whether I was using the Finale or ARIA mixer, with too many other consistent variables to be coincidence.