Ticking under hood, but not the engine itself...

[synnyzter]

Bought a used Blazer and it makes this ticking noise than I cannon pinpoint. I recorded it via video so you can hear it so I am really hoping it helps at all but I do understand listening to a video isn't the best option, but it's worth a shot I figured.

http://youtu.be/5G_AKovsTdU

I never heard a sound quite like this one but I am thinking it's the fan clutch although there is no play on the fan nor any fluids leaking, it also has decent resistance when I spin it by hand. It ticks like that at all RPM's until it gets to a high temp then is ONLY ticks at a higher than idle RPM. Any ideas at all so I can at least eliminate some options? Thanks in advanced.