I have a 2016 Miramar 34.4 and have had a few issues but nothing like what you're experiencing. A couple of things to check...the outside kitchen drain (assuming you have that kitchen) was there but not connected and the bracket that supports the rising TV only had one screw in place. The others were laying on the floor. As a result of finding those issues I removed every drawer and access panel and stuck my head everywhere I could get it. Found many missing or loose screws...this probably saved many problems down the road.
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