Volvo Repair: brake booster repair, vacuum leak, independent repair

Question
Intermittently, there is a hissing noise under the driver side dash when I release
the brakes. It sounds like a vacuum leak. It stops if I apply the brake. I'm
guessing it's to do with the brake booster.  Is there a way for me to check
whether it's a hose problem or something I can fix myself before I have to take it
to the dealer and spend $1,000 on having a new booster put in?

Answer
  Casper, inspect the lines going in and out of the booster. Replace any that are cracked/torn or visibly leaking. Other than that, replacement is the only option. You might be able to find an independent repair facility to do it for a little less?

Mark