Adjusting sync volume

Is there a secret way to changing and adjusting the volume of the sync “pulse” coming out of the POs when in sync mode? It seems like it’s independent of the actual PO volume adjustments (BPM+numbers).

it is fixed at the maximum volume it can generate.
u would need an external piece of gear to amplify or attentuate


In case I need to amplify that, do you have any suggested portable/small devices that can do that?