Air in Line of Kitchen Sink

Newb and inept here, any replies appreciated!

We have air in the line of kitchen sink. When the sink is at full blast, it "thuds" roughly every second and decreases in frequency the slower the flow of water is from the faucet.

We have tried to fix it by opening all the faucets and toilets and letting them run for about 15 minutes, but that only increased the frequency.

I'd really like to avoid paying a plumber, so again, any advice is appreciated.

Thanks!

You do not have "air in the line". If you have a sprayer attachment, your diverter is bad. Or you have a bad washer in a shut-off.