Here's a screen recording of the issue:
I have two filters, both the exact same. One is on the group FX, one is on the main FX. When I use the group one, it sounds fine. When I use the instrument one, there's a noticeable popping sound both when I press the key down and when I release the key. I have to increase the release time to 100+ ms to get the popping sound to go away. It also doesn't makes sense why the release time would affect the pop from the key press (as opposed to attack). Any explanation?