Hi to all. So my brakes aren't working properly. When I apply pressure to the brake pedal , I can hear air, a sort of hissing sound from behind the brake pedal. I don't think it's the booster or master cylinder because I'm not losing any brake fluid and the bake pedal isn't high or hard. The brakes pads are new. So it's not that. And the hissing sound makes me suspect an vacuum leak maybe? Should I bleed the brakes first? Any help to help me find and diagnose the problem,any insight or suggestions are greatly appreciated. Go easy on me, I'm a woman😜