@Gestour @RailfanEthan The solutions the two of you gave work but I have the best solution that has not let my down to date:
The reason this is happening is the plane takes too high aoa's while pitching, and then one of the two wings, most likely the one lower stalls and the stall causes a roll. The fix? Make the main wings bigger, make the horizontal stabilizer smaller (or it is a rotator, reduce the angles) and optionally add AoA limitor.

Thanks! I placed the wings and added more fuel to do what you said, and it performs just fine now! @randomusername

My simple answers: snap rolls but happening due to high speeds

Does it auto roll in normal flight?
Yes- uneven weight or drag
No- poor balance

It's usually related to how you mirrored your parts. Mirror the plane twice on the left and right. This will probably be fixed in the next update.

@IssaIwan There are a number of things that could be causing it. The only way I have found to avoid it is to test your plane often, like every 5 parts, flight test. Then, when roll shows up, you just undo a few parts.

This only happens with jets. I've never seen prop planes randomly roll.