My track bike has been making a funny creaking noise in the crank/bb area the past couple of days. It happens at pretty much the same point of rotation, almost only when im putting pressure on the cranks. I tore apart my bb today and repacked it, same noise. I have a set of what appeared to be lightly used Campy strada cranks on it with a Miche bottom bracket. My friend suggested that the taper on the cranks might be worn, causing the creaking. Is that possible? Any other ideas?