Talon T-38A - pitch and roll trim?

I understand how to set an attitude and airspeed and then trim out stick inputs so the stick stays neutral in both pitch and trim. I can make that happen... BUT

within 10-seconds the plane is changing it's pitch and roll. And, the change becomes exponentially greater. Sometimes it is positive and sometimes negative.

Aileron trim is incredibly sensitive - I hover the cursor over the roll trim and it shows 0 - if I click it once it shows 0.1 and if I leave it there the plane completes an aileron roll in about 30-seconds.

The pitch trim is not as sensitive but the following is way to common:

Straight and level with -3% elevator trim - 540 knots IAS at FL250. I change the pitch trim to -2.5% and within 20 seconds I see a climb of 4000 fpm. The same happens going down ward.

I am using a Bravo trim wheel for the pitch and have it set so one-button click is 0.2% - or it takes five clicks to change the trim by 1%.

I have spent a dozen hours trying to work this out - with no luck.

I am quite proficient with the Lear 35, the L39, the BAE Hawk, and the A-10 - but can't keep the T-38A stable.

What am I doing wrong?

Edited 1 hour ago1 hr by TacomaSailor
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