Vacuum sound inside cab when brakes pushed 2008 xb

When I push breaks down I hear a vacuum noise from within the cab and idle power loss.

No loss of brake fluids..

I have only worked on my cars, so am not an expert and would appreciate some opinions.:)

https://www.youtube.com/watch?v=Okj7T9BNERk&ab_channel=Zerojoshua

Thanks!

Brake booster issue. May be just a cracked hose.