Manufacturing issues typically rear their heads in a relatively short time period. After that, it is usually either a design issue or component failure. Nine years after manufacture, I’m betting on the latter…
When the car behaves differently than when it was newer, you can bet something is wrong with it. Then, you need someone sufficiently knowledgeable to track down the problem and fix it. Most customers will balk at a labor intensive search that may result in only a cheap part being replaced. But sometimes, that’s what it takes. I tracked down a parasitic drain issue with my prior TB that turned out to be a result of a partial failure of a resettable breaker that feeds one of the electric seats.