b300 built in solar controller overnight drain?

I have an ac300 with 2 b300 batteries. I have the 2 solar inputs on the ac300 maxed out.
I just added 200w to the solar in on one of the b300 batteries. No matter which one I hook it up to, after a day, it’s percentage is lower than the other(-2 to -4 %) even if it started out higher(+2 to +4%) from testing the opposite battery the day before

it’s 2x as worse if i put one of those in-line power meters in to monitor things. (-8 to -10%)

I know the controller in the battery is not as good as the main unit, but this reminds me of my early days of smaller portable solar generators that would drain with solar hooked up overnight…

Anyone else have experience with this issue? I’m thinking of trying to put a blocking diode in to see if that helps?

@bluetti_shiftzoomzoomgmailcom I assume battery pack A and battery pack B. Do you mean that no matter which battery pack the PV is connected to, battery pack A will lose power faster than battery pack B? Have all battery packs been upgraded to the latest firmware?