atwood jack popping noise

If you sheared a pin, you will know it because you can move the jack up and down with your hands. More than likely, the atwood 'brain' is confused. I have the same jacks as you and put up with this problem for several years, BUT atwood has a new system that replaces systems for the few years they had the jacks you and I have--it isn't free but a qualified atwood place can replace them at a discount rate. The replacement involves four new jacks, a new brain that will NOT allow for over extension and a new panel. I don't know where you are located, but there is a guy just north of Salt Lake in Sunset who has changed out the Tiffin '07 jacks. He has been approved by atwood. It is Charlies Service and the guy who does the 'change out is Justin Dubois. If you want his information, email me privately at hsteinle@hbsteinle.com
In the meantime there are a couple of things you can do, BUT you'll more than likely continue to have repeated problems until you change out the system. Unplugging will sometimes 'fix' the problem for the time being. Also, Putting your foot on the brake and putting coach in gear sometimes works.

Check page 5 of the Levelegs manual for the troubleshooting instructions of the system. It sounds like you may have sheared a pin.