I don’t see anything about jumpers in the PDF manual. Could you make a copy of the printed manual page and post it?
If you use the potentiometer, you may have a look at Analog Input Settings PD070 – PD076. I would set PD073 (Lower Analog Frequency) to “133” or “140” and PD072 (Higher Analog Frequency) to “400” accordingly to your spindles rated highest and lowest speed. Default in the VFD is “50” which could be the reason why the potentiometer sets speed too low.