Sound from the 981

[equ]

The boxster started making a sound last week. It was about 50 or 100mi after I switched to the winter set, so I removed and reinstalled carefully. No change.

It's on the RHS only, I can't be sure if it is from the front or the rear. My first guess was a pebble between a rotor and the dust shield behind it which is super close. I looked, could not see it. I don't trust my lift, I took it to a tire shop and they looked, could not find a cause. They did not disassemble my calipers.

It's mostly at very low speeds and not always audible. It seems to come on when the car has been driven and it slows down. Nothing with engine, it goes with rotation, but not a wheel bearing. When I do hear it, it's worryingly crunchy, if it's not a stuck stone, I'm worried a bolt or a pin is backing out and scoring a rotor. But then it goes away at times, mostly when it's colder. I think it's the brakes as when I get on the brakes, the sound disappears. I also don't hear it at higher speeds, 40mph+.

I had work deadlines through Friday so had no time to call or go by shops. I guess I will try to troubleshoot it this coming week that I have off. It's also due for brake fluid at this point. I still have a lot of pad life visually at 30k miles. All parts are original to my knowledge at ten years old. Perhaps there is a stuck stone I cannot see? Or I lightly knocked something when I swapped wheels? Tire shop felt a lip on the rotors, thought the pad could make sounds.