Brake "whistle" noise

[Houston]

I have this weird, intermittent brake noise problem with my '09 Vibe. It isn't the normal screeching we sometimes hear. It's more of a whistle-type noise heard just before the car comes to a stop. I'm hard of hearing, but even with that this noise is loud. I just got back from the dealer. Wouldn't you know it, but the noise didn't occur while there. They checked over everything and roughed up the pads (I watched), hoping that would correct the problem. But, darn it, as soon as I slowed to enter my garage at home, there was that darned, loud "whistle-type" noise again! It is definitely connected with when the brakes are applied - but is heard only immediately before it comes to a stop - and doesn't happen all the time. Are there any vacuum connections that might cause this?I'm stumped. So is the dealer. Do any of you have an idea of what it might be?

[Sublimewind]

Did they apply any 'brake quiet" paste to the back side of the pads? That you know of? that is usually the culprit, but i can't imagine then NOT putting some on, with complaint of brakes making noise..

[Houston]

I really don't know whether they did. I'll contact them tomorrow (Monday).Thanks!