Oh! You're right. Never mind...
It looks like that board has on-board drivers, but still uses pots to set the motor current. In that case, try turning the current down until the motors skip steps, then turn it back up a little until they stop skipping.
It looks like that board has on-board drivers, but still uses pots to set the motor current. In that case, try turning the current down until the motors skip steps, then turn it back up a little until they stop skipping.