BuddyPress.org

Here is the code I used. Put this in bp-custom.php in your plugins folder, and it should correctly display your user’s BP avatar across an entire WordPress MU install. Lemme know if it works!

function nfm_bp_avtar_upload_path_correct($path){
if ( bp_core_is_multisite() ){
$path = ABSPATH . get_blog_option( BP_ROOT_BLOG, ‘upload_path’ );
}
return $path;
}
add_filter(‘bp_core_avatar_upload_path’, ‘nfm_bp_avtar_upload_path_correct’, 1);

function nfm_bp_avatar_upload_url_correct($url){
if ( bp_core_is_multisite() ){
$url = get_blog_option( BP_ROOT_BLOG, ‘siteurl’ ) . “/wp-content/uploads/”;
}
return $url;
}
add_filter(‘bp_core_avatar_url’, ‘nfm_bp_avatar_upload_url_correct’, 1);

Originally found here: https://buddypress.org/community/groups/how-to-and-troubleshooting/forum/topic/custom-avatars-arent-shown-on-single-blogs-in-wpmu/