I have a 2001 Ford Escape 4x4 with 78k miles. I get a hiss in the cabin intermittently that is relieved only by stepping on the brake.
Brake function is fine. No change in pedal travel or braking ability. The sound is not always there. I replaced front pads and rotors at 60k. 6months ago, I had a very slow leak from a seam of the brake fluid resevoir and replaced it. I bled all lines. All was well for months.
Any ideas? Thanks, JK