Header can't be modifed

I'm getting the following error

warning: Cannot modify header information - headers already sent by (output started at /var/www/html/dev/modules/paging/paging.module:68) in /var/www/html/dev/includes/common.inc on line 247.

Not sure if this is a problem with the paging module or in core. It is happening in administration/modules when trying to install/uninstall a module. After hitting the submit there is a blank page, you can then go to the main page and that's where the warning gets displayed. This is also on a test site using the front_page module and 4.7.0 from cvs downloaded today.

Started immediated after activating the paging module.