Sawmill,
That is called dynamic braking, on those models they made an error in the design and it's not adjustable or variable, and there is no fix for the problem.
There was a lot of talk about that exact problem when they came out, it's a design defect that was cured on the next model.
If it has gotten notably worse than it was previously you could have a dampener that has failed, that will amplify the problem.
Mike,
Your model should not have that problem, there is either an adjustment issues or a part failure.
If your friend's BX is not a 24 or a BX**50 model then it too needs looked at.