A very strange problem with tempo track and MIDI

I’m not sure how to explain this but I will do my best.

I am writing a MIDI orchestral arrangement. I am using the tempo track. Quite randomly, I noticed that at one point the tempo track graphical points goes alllll the way up to the top and back to the normal tempo within a matter of a second or two. It looks like the tempo track line had a seizure. I thought it was odd, because I never did that, and I did NOT notice a crazy tempo change in the song at that point.

The best way to describe the way it looked is an upside down U

So naturally, I moved the point back down to where the tempo was supposed to be, evening out that ridiculous cubase tempo fart.

When I evened it out, the tempo at that point goes BERZERK! So I undid it and let the weird ass tempo stay. Makes no sense.

But here’s where it gets weird. When I write different MIDI arrangements over that part, they respond to the weird tempo change, while the OLD MIDI parts do NOT respond to the tempo change. So essentially, I cannot write anything new at that part because the new MIDI will reflect the tempo fart while what was written previously won’t even acknowledge the tempo fart.

Even stranger, when I select all the MIDI tracks to move over as far away from the tempo fart as I possibly can, all of the MIDI that did NOT respond to the weird tempo change had now reflected the tempo change as if it were still there. It’s as if it is actually embedded into the MIDI data. It sounds terrible. I cannot move the MIDI anywhere now without it reflecting that tempo change as if it’s embedded in the MIDI.

And your used software is…?
Disaable musical timebase on all MIDI tracks, eliminate the " tempo farts" re- enable musical timebase, if needed.