edmontondown 发表于 2013-1-2 23:56 G* m* V! H( A" t& J
yes, may have something fell down on the other end of the hood vent
0 t/ ~. Q0 s& t6 i0 u7 TAt 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.