edmontondown 发表于 2013-1-2 23:56 + D# D% y+ U3 L: P! m; S) M1 W
yes, may have something fell down on the other end of the hood vent
4 i# b* f2 X: Y2 V" e O
At 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.