I have a 48V system and 4 parallel banks of batteries. I've just connected my 3 balancers (they were just sitting on the wall for almost 3 years since the system installation, just because the certified Victron installer failed to make them work!!!). So, I've extended the diagram available in the manual as attached. 3 out of 4 sets are having now the same voltage, only one set is having 50mV lower voltage. And "high voltage on the upper battery" led is lit, but just on the first balancer, not on all 3. Anything wrong on the installation?