2003 Sebring; 2.7 engine; automatic....I hear a strange 'pop' under the dashboard, behind the instrument cluster sometimes when I hit the brakes. Only happens in stop and go traffic when I press the pedal there is a popping or snapping sound under the dashboard. Not every time and usually when I hit the brakes gently/slowly. Brake fluid is at normal level and the brakes seem to work just fine. What could be causing this sound? Thanks.

 

It's almost impossible to diagnose an "odd" sound over the internet, but I would start by checking the linkage and support of the brake pedal. Look for anything loose or missing. Observe the motion of the pedal.
There could also be something loose or disconnected between the pedal and the power brake booster. You may not be able to see that at all.