It does sound somewhat like a bad CV joint when you say it goes away when you let off the gas, as this unloads the joint and allows it to float more in the middle rather than pushing it into the worn area where it's out of alignment. It's usually the outer joints that fail first because they see more angularity. If you can find an empty parking lot or a cul-da-sac try making some tight turns (steering wheel locked all the way to one side or the other) while accelerating from a slow speed/stop. You'll want to be listening to the joint of the inside wheel of the turn as the inside wheel is angled more than the outside wheel during a turn, putting more stress on that CV joint, and this is when you'll be able to notice the popping/clicking the most.