You can take it apart. Pull the stem and see if anything is loose or worn on the inside. If loose, then repair and reassemble.

If broken or worn, or things just don't go your way, you can get a vacuum break repair kit and swap that out for the old.

Or just buy a completely new bib and swap out the old for the new.

"Or just buy a completely new bib and swap out the old for the new."

Just hope the valve installed now is screwed in and not soldered.

I have seen more hose valves soldered in with the joint buried behind things like tile than you can shake a stick at.

Please tell me where I can get parts for asse 1019 frost free faucet...thank you...

I just repaired one made by them (B & K Industries), which are the ones you see in home depot. In my case, it was leaking so the stem was replaced, too, which meant I needed the model number to get the correct length stem & cartridge replacement. They also sent a replacement cap and assembly underneath.

In your case, it sounds like just the parts under the cap need to be replaced. Again, if the mfr is B & K Industries, they will send a free replacement. Or you could splurge on a new one to take off the cap and guts. To do so, don't grab the nylon threads. Instead, use tow two slotted (standard) screwdrivers inserted into the air hole slots and turn it. Good luck.