Noises can be difficult to find. Last year while riding to my doctor appointment I was hearing a rythmic sound. In time with my right leg. Sort of a crackling sound. I couldn’t figure it out. I parked my bike and went in, as I sat down in the waiting room I heard that sound. Huh? Seems that a paper in my jacket pocket was crinkling and making the noise. The other patients were surprised when I jumped up with a loud Ah Hah! Found it!

BTW - that list is really good.
Also BTW - that was the waiting room for mental health services among other things. I suppose I was already suspect for arriving in bike clothes so any further antics could be expected. Ha ha!