Happened to me on my 2000 Magna. It was the connection of the flex drain hose to the hard pipe at the rear of the compartment. Took the coach to Edmundson RV in Edinburgh, Indiana. They removed a small plexi panel (about 5" X 6") from the edge of the slide and cut the 1000 or so wire ties
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The tech removed the upper panel that faces you in the compartment behind the slide and extended the hard pipe an inch or so. This allowed more of the flex hose to be inserted into the hard pipe. The original configuration had less than one inch inserted in the hard pipe. Removing the small plexi panel allowed the tech to cut the wire ties, add adhesive to the flex hose and hard pipe connection and replace the wire ties.
I don't have a copy of the bill but I believe it was about 4 hours labor.