First time posting but I've been reading the forum for a couple years.
I have an Infinity sub and a Yamaha receiver. Both a couple years old. When I change the source on the receiver (tuner, dvd, tv) there is a sound that comes from the subwoofer, sort of like a pop/puff. When I disconnect the sub the sound does not come out of my floor standing speakers. Is the receiver sending something out on low frequency that only the sub can pick up?
