I have the same thing going on with my 2012 Alpine. It all started on the way home from the dealer. I thought I was doing something wrong but when I got home I called and they said it was air. I ran them in and out several times then a short road trip. Same thing. I took it back to the dealer, stopping twice on the 60 mile trip to close the slides. They had it a couple weeks and I got it back, supposedly fixed. I drove around a bit and seemed ok.
Then our first camping trip. Made the 200 mile trip there just fine. On the way home, I really wasn't paying much attention for the first 30 miles or so and I looked back and the bedroom slide was out about 18" and both living room slides were out 12". Its a good thing I wasn't on a two lane, someone could have gotten hurt. I had to stop every 15-20 miles to close them. It went back to the dealer, they had it for about a month to fix it. I finally got it back late fall. At least they winterized it for free.
Fast forward to yesterday. After one twenty mile test trip last fall, it sat all winter. I had to move it yesterday to get it cleaned up for the season. I moved it all of about 150' and guess what, the bedroom slide was open about 4". I emailed Keystone and the dealer yesteday (Sunday) with my problem. The dealer called this morning and they are on their way to pick it up. He told me the Lippert rep was in two weeks ago and he discussed my camper. Are they using mine as a training aid? Anyway, it will probably be gone for awhile again. I will try to be patient. The service tech did ask one question that struck a nerve, "is there anything else that needs to be looked at?" How would I know, only been camping once in the 8 months I have owned it.
As for Waltec's approach, I am glad it was that simple for him, but that obviously won't fix mine. After stopping multiple times on the trip home last fall, it won't stay closed after re-pressurizing. Installing load locks on three slides every time I travel? I won't settle for that. Lets see what Keystone/dealer can come up with this time.