I heard this but with a new microfiberNice bass! Welcome to the club!
If the pickups are factory they will be passive and neodymium. The preamp would be EMG.
Your bass should run in passive without a battery if all is factory wiring. Perhaps popping the cavity cover off and posting a photo could help.
It should also be quite silent which does raise the question of, “have any kids been done?”
That or worn pots or just static? I hear a bounce sheet wipe down will help remove static which can happen on basses with pick guards