Forum avatars not showing up in some places (calls unknown.gif instead)

[محروم.كوم]

Upgraded from 3.7.4 to 4.0.2pl1 and I'm trying to figure out why avatars are not showing up in some places.
Under maintenance I've rebuilt both avatar thumbnails and custom avatar thumbnails with no errors, twice.

In CMS article comments, no avatar.

In blog posts, I do get an avatar.

Also, on the profile page there are two alt tags which reference "username's avatar" - but the bottom image loads the avatar whereas the top avatar loads unknown.gif.

Edit: there seems to be some confusion between where a profile pic is used and where an avatar is used. I just realized that the top photo with the alt tag "(my username)'s avatar" is actually where the profile pic appears when there is one. When there isn't one it loads unknown.gif but with the alt tag of "username's avatar" which is misleading. Also the avatar in the cms article comments seems to be pulling from the profile pic rather than the avatar.

I've upgraded from a previous version, but I'm using the 4.0.2pl1 style completely (nothing imported for the style.) Is there a setting somewhere I've missed which would unify using the avatar for avatar site wide instead of trying to pull the profile pic in the cms comments for example? Or should I just go into the templates? __DEFINE_LIKE_SHARE__