I have a ticking in my gear as well. For the longest time I couldn't figure out what it was. It was rhythmic so I thought it might be a clock or something. Turns out the electric fence around my horse fields was causing the audible tick in my gear. If I unplug the electric fence transformer the ticking stops. Those fences arent constantly electrified. It sends a shock through the fence every second. Something like that might be causing your audile artifact as well.