there, i'm using membership with buddypress plugins on my

hi there,
i'm using membership with buddypress plugins on my site.
i have the latest wordpress and all plugins up to date.
buddypress is supposed to have that @mentions functionality but when i start typing in @... it just doesn't do anything.
i'm mentioning someone, publish it and it still works, but i get this message:

Warning: sprintf(): Too few arguments in /home/platne/promocjamuzyczna/public_html/mysite.com/wp-content/plugins/buddypress/bp-activity/bp-activity-notifications.php on line 94

i've tried to disable all plugins but still the same issue. any ideas why that happens?

thanks,
Adam

PS. i'm using Dynamix template which is buddypress compatible. however, i've tried twenty thirteen and mentions seem to work.