Well, whether it is to be called a clunking or clicking sound or something else is in the ear of the beholder. All I wanted to point out is that there is a different type of background sound apart from the voice.
I think both sounds are quite audible, but while the voice is pleasant the other one is a bit distracting. That's why I wanted to know if it was inserted on purpose or is some sort of artifact.
Anyway, thanks for Eye-Bo, I enjoy using it.