We just experienced something similar not too long ago. Our front legs starting "drifting" and every fifteen minutes.
I called Mr Ed (@DRV) for tips, he referred me to Lippert, after talking to their customer service dude I learned the draw tube on the reservoir only extends to the half way mark on the tank. Lippert told me to put the truck under the trailer and bring everything up and in and I should be within 1/2" of the top of the tank. I was 2" low! After adding almost two full quarts of fluid and running the slides and landing gear in & out and up & down several times we were good to go! Problem solved!
Run everything in and up and check your fluid level, hopefully your problem was as easy as mine!
Dan