Annette, not up on California wildlife but if it were here I would definitely say that you have flying squirrels. The tell tale is two part, nocturnal activity and the rolling sounds. That is them rolling acorns or other nuts as they store them in your attic for their winter cache.
If not fliers then another small rodent with a similar habit.
Standard victor rat snap traps with the large yellow pan beat all other traps hands down for fliers. For bait I use a mix of commercial nut oil based blends, pecans, black walnut oil in a peanut butter base. The exact recipe is a trade secret.
I do not recommend straight peanut butter as it is effective only for mice. Squirrels and rats will investigate it but do not find it all that attractive.
The trick to snagging fliers though is trap placement. They can be as bad as any trap shy coyote. You have to locate the exact areas the fliers are using and place accordingly. This often means the tightest spots in the attic along the outer edges in and adjacent to the soffits. Seriously, I had one job where the width of one 2"x4" was the difference. For two weeks I went without catching a single flier out of this attic. My traps were tight to the sill plate that the rafters rested on. Every night of those two weeks the client heard the little buggers running in the vinyl soffits. Finally out of frustration I got down on my fat belly and shifted the traps to the other side of the sill plate so they were down in the soffit. That very night I nailed three and closed the job three days later.
I've gotten a lot better since then. I've got a job open now with eight down in the first three days.
Once all the rodents are gone you are going to have to have an exclusion done on your home. An exclusion is trade lingo for a complete structural seal to prevent entry by wildlife. I can not stress it highly enough that this must be done. Once you have had a wildlife issue inside a structure that structure will continue to have a wildlife problem. It is the exact same concept as bees being att