Hissing noise while braking

My guess is i've got a leak in the vacuum booster. First of all, I have not poked around on it, but will this weekend.

Secondly, I've got significant pedal travel, which i know could be the result of air in the lines, worn pads, or some other trouble. But the hiss is easy to hear when stopped. The harder i press the pedal, the more pronounced the hiss.

So does the hissing noise typically indicate that the booster is shot internally?? And a new booster is required? Assuming I dont have a vacuum hose leak, something tells me that's the case....

Thanks!

Check the hose under the dash from your brake pedal.

Thanks! I'll do that. The hissing does seem to be in the footwell. But heck, I could just be hearing it through the firewall...

I will check and report back.