I've had some squeaking coming from my front passenger wheel a couple of times now. It's regardless of whether I'm braking or cruising, and it doesn't seem to matter how fast I am going either. Last time it happened, I was cruising on the highway and just started all of a sudden. I pulled over to try to check it out, couldn't see anything obvious. Went back on the road, and after another minute or so it was gone. Is it maybe just some dirt and dust that's causing it?