Is my SBC getting weak?

The SBC starts quite often-- if the engine is running car in neutral, every 2 time I step on brake I can hear ""brrrrrr". when the car is left in garage engine is off and key on, every 5 minutes I can hear the same sound.
Dealer confirmed my car SBC is slightly noisier than normal, but said they can't do anything until I see ""visit shop" sign.
I did search some people say SBC should start every 4 times brake action, and the pump noise is hard to notice.
are these indication of my SBC getting weak? Thanks.

I can live with the noise. I'm more worried about the running frequency of SBC pump. It starts every another time brake pedal applied. Is it too often?
A recent full STAR flush seemed to help it pump less frequently in my '03 e500. I never really paid attention to it, so it could just be in my head.
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If it's still making a lot of noise after the firmware upgrade, you can have the suction damper installed and it'll be completely quiet.

I did ask my dealer to check possible FW upgrade and was told no for my car. They charged 1 hr for diagnose though. I paid $160 for a car wash.



Damper hose was installed(at factory I guess).

The diagnose seems ok only failed one item which reported possibly air in brake system.



