edmontondown 发表于 2013-1-2 23:56 9 |) |: v6 o9 m; f
yes, may have something fell down on the other end of the hood vent
. F: g# r2 S0 [2 _3 vAt 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.