Sorry for the very late response. I suspect the source of the ticking is interference from the digital usb signals being picked up by your analog audio.
I am going to guess that a) this is a desktop/tower box b) the headphone are plugged into a front/top panel that also includes a usb port or two c) internally, the audio cable from the mobo -> the panel runs parallel to the usb cable from the mobo -> front panel. You are hearing udisks periodically probe the usb port. Tom -- Thomas Caswell tcasw...@gmail.com
