Clicking you can hear and feel in clutch pedal
 

Hello everyone. Maybe someone can help me narrow down the possibilities for a clicking noise I have. I've search the forums but haven't been able to find any definite answers.

I have a 2006 6MT 350z. The issue I'm having is that there is a mildly audible, rhythmic clicking noise that can be heard at times under load at lower rpms. It increases in rhythm as rpms increase. It sounds as if it comes from the drivers side brake/clutch master cylinder area(though it could be reverberating from elsewhere).
If you lightly place your foot on the clutch pedal, you can feel the clicking in the pedal. If you fully press the clutch pedal the sound goes away. The clicking is not present when the car is idling or being revved in neutral.
It's not constantly present, but seems to occur more in cooler temps.
The clutch master cylinder, clutch lines, and slave cylinder were all replaced last summer to resolve some pedal drop issues. The clicking was first heard just before that work was done, so I don't think the new parts are the cause.
Other mods are Intake, high flow cats, cat back dual exhaust.
Car has 75,000 miles on it and I believe the original clutch. I've driven 350s with aftermarket clutch/flywheel setups and mine feels stock.(Though I've never had the tranni out to be certain)
Any thoughts?

mine clicks too. 07 nismo 47k. did it when I bought with 36k no issues just a click sound and feel