Last year I was startled awake by a different noise in my Heating in addition to A/C vent in addition to it took me several minutes to figure out what I was hearing. Initially, I thought that maybe an seasoned sock or something had gotten into the vent in addition to was flapping around. Then, after a bit, I realize that the sound must be some kind of an critter, perhaps a bird, that had gotten stuck into the air duct, and but then my buddy and I heard a squeaking sound, almost like a mouse makes, in addition to then my buddy and I realized it must be a bat that was in my Heating in addition to A/C vent system. I did not sleep anymore that night. After a while, the fluttering calm down but it did not go away entirely. I called up critter control but they requested I call a pest repair instead. The pest repair came out in addition to they set up traps to get the bats out of my attic in addition to relocate them. Evidently, my attic was infested with bats. They also took apart my entire ventilation system in addition to it detached some of the bats; Finally, the bats were all gone in addition to I had to hire an Heating in addition to A/C contractor to come in addition to repair the vents that the bats head been in. I also wanted a thorough air duct cleaning as I was distraught that I had been breathing all of that bat guano for months on end. I also hired a professional cleaner to clean up my attic. It cost me a lot of money for everything to be cleaned in addition to the bets to be rehomed like they were but now my attic is sealed off in addition to it should not happen ever again. What a nightmare this was.