depends on your PAP, axis tilt and rotation.
12 mph is VERY, VERY SLOW.
Are you sure aout that ball speed?
Basically, the pin needs to be lower, exactly where depends on your PAP.
I'd also guess you might need more surface, but that depends on the other factors. Can't use too much surface with too little ball speed.
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"...for advice is a dangerous gift, even from the wise to the wise...."
J. R. R. Tolkien