Fuel Pump Noise?

[dbrick]

2007 R1200R, fuel pump replaced six months ago (at 38K) as part of BMW's pump boss recall.

I rode the bike to lunch today, about 10 miles on the freeway. During the final few blocks (at low speed), and after putting the bike on the stand with the motor still running, I could hear a faint high-pitch screeching noise. My riding partner described the noise as the sound of metal sliding on metal. It wasn't terribly loud, and didn't relate to engine rpm. Both of us thought it was coming from the fuel tank, which had been filled just 10 miles before. When I got home (another 10 miles), the noise was absent.

We both suspect the fuel pump. I've still got 18 months on BMW's parts warranty from the recall work. But I'm curious: have any of you heard this sort of noise? What did it turn out to be?