CV shafts can piss you off... I had one that would only click after it had warmed up for about 15 miles of driving at a decent clip. And then, it would only click if I really stepped on the gas as slower speeds (probably because the car makes enough noise I couldn't hear it going fast).
So often it wouldn't even click. And when it did, I'd try to diagnose it the next day and have a hell of a time making it happen again...
I just guessed CV because I have so much trouble with them, but they can be really annoying.
You can usually hear which side is making a noise. But if you can't this is a good time of year to test it...
Find a place where you can put one wheel on something with good traction, and the other wheel on ice. Give it hell. You'll only spin one tire, so hopefully you can get a CV click and isolate the side.