I was using a raspberry pi 3b+ connected to a smart shunt 500 and had no issues. I added a new 150/70 MPPT controller and now the smart shunt 500 has random disconnects. I tried switching USB ports and switching the power supply (I am using the official raspberry pi power supply as well as another 2.4amp power supply) with the same disconnects. I did make my own USB cables, but the smart shunt works fine when the MPPT is not connected. Do you think the raspberry PI needs an external powered USB hub to connect multiple devices?