edmontondown 发表于 2013-1-2 23:56 ) z: |: }, ?* d& k( E8 u: w7 ^4 b! ]yes, may have something fell down on the other end of the hood vent
$ G$ F6 ?8 P) M7 g/ p6 J2 kAt the other end(outside) of the vent duct, there is usually a metal cover for the opening, it can swing up and down and if it is a windy day, it will be blown swinging, thus making a kind of banging noise.