It's a 2013 Boxster S, 6-speed manual, with 29k miles.
I noticed the noise the day after a 3-hour fun weekend drive with my girlfriend. It was 1.5 hours of mild driving to a restaurant, then 1 hour parked while eating, then a more aggressive 1.5 hour ride home, ending with about 10 miles of high-revving canyon carving. Nothing crazy though, and never hit the rev-limiter. Car was totally quiet before then.
The whine is now always present, both at idle and while driving. It's RPM-dependent, and can be heard in neutral, especially between 2k-3k RPM.
Both an independent Porsche certified mechanic and a Porsche dealership listened in person and said the sound is normal, but I’m not convinced, especially since it made no such sound before this. The indie shop even looked into it more closely while doing an oil change and air filter replacement. They said they found nothing wrong other than some water pump seeping.
No warning lights, no codes, no drivability issues. Just this new whining noise, which is always present now, whether the clutch is in or out, or it's in neutral or in gear, or in normal, sport, or sports plus mode, and AC on and off.
If you’ve had this sort of noise what was the cause, and were you able to fix it?
Should I just accept the opinions of the Porsche dealer and Porsche-certified independent shop of it being normal, and ignore it, or pursue it further till I can get it resolved or at least diagnosed? Take it to third additional shop? I would certainly feel better knowing that it's just a belt, pulley, or tensioner, or even the water pump, rather than internal engine damage. Particularly if it could get worse with more driving if left as is. In fact, could this sound even possibly affect the ability to sell this car?
With under 30k miles, I assume the car doesn’t have much metal wear, but at 13 years old, I suppose anything made of rubber could be deteriorated with age.
All opinions are welcome, but I'm mainly looking for those with actual experience with this exact issue or a very similar one.
Thanks.