I have been plagued with slide leaks for the entire first your of owning my 23IKSS with has two slide outs. The trailer has been at the dealer a total of 6 of the past 12 months. (but this include over the winter up north here where I would not have used it anyway). The patched and caulked, etc but cannot seem to fix it. I contacted Forest River warranty department a couple times during this time and they have now agreed to have me take it back to the factory for a real repair job, new seals and water pressure test. Goes in on Wednesday while I am driving through Indiana anyway. The factory warranty people seem very nice and are accommodating my schedule so I can drop it off heading west and pick it up on my way home three weeks later.
I suggest you keep on this with the dealer and if that does not work do not hesitate to contact the factory. Luckily mine only leaks when I drive in heavy rain.
2015 Roo 23IKSS
2016 F150 SuperCrew 3.5 EcoBoost