You have a problem I've never run into but I do have a couple of thoughts.
First, are you sure the pads are at fault not the wheel bearings? The way the pads are built, the warning bars are meant to drag along the rotors when the pads are worn out. The scraping/squealing noise is obvious and not in my experience a clicking sound. That said if the clicking goes away when you apply the brakes, it is likely the pads. To check the pads you can always apply a thin coat of paint to the edge of the warning bars where they would meet the rotors. After driving, if the paint isn't scraped away, something else is going on.
I assume you've spun the wheels with the front end off the ground to see if you can isolate the clicking.
Second, did you install new hardware with the pads? It's possible the clicking is the result of some sloppiness in the hardware.
Third is a dumb question but did you put wheels on that are for a disc brake car? if not, check the inside of the wheels for shiny spots indicating interference.
If it were my car, after making these checks, I'd install a different brand of pads.