I run this multisite network, and i get this warning now

Hi guys,

I run this multisite network, and i get this warning now when i start up new users.

header information - headers already sent by (output started at /var/sites/p/problockster.com/public_html/wp-content/themes/Divi/functions.php:82) in /var/sites/p/problockster.com/public_html/wp-includes/option.php on line 772

Warning: Cannot modify header information - headers already sent by (output started at /var/sites/p/problockster.com/public_html/wp-content/themes/Divi/functions.php:82) in /var/sites/p/problockster.com/public_html/wp-includes/option.php on line 773

any idea what is causing this, it used to work nicely....