Anti siphon not quite right.
Usually just a minor obstruction. At least it was pointed toward the sink 
The guy at Home Depot told the Home Owner that “they all spit water” when the Home Owner bought this brand new one. The Home Owner came in to ask me about this just as this was happening, very funny, I rarely get a picture of it. I explained the hose to the garbage disposal was probably partially blocked.
Johnny homeowner usually forgets to punch out the knock out before attatching the airgap to the disposal. Oh what fun
It’s Not always Johnny Homeowner who forgets to knock out the plugs. I’ve seen it on new contruction also. In a new Apartment complex the plumbers failed to knock out the plugs in more than half the Garbage disposals and no one picked it up on the Punch List, it was not discovered until people began moving into the Apartments and the Water began hitting the Ceilings, the Plumbers also failed to tighten the tank mounting bolts on more than half the toilets, they were tight enough not to leak until someone sat down an leaned back a little, believe it or not the builder used the same plumber on his next project with about the same results…the Cheapest Bid will get you almost every time.
I had one a couple of weeks ago that was spitting water over the sink and onto the floor! :shock: