[SOLVED] Blank admin page on second site when using core multisite

[Arctic]

Resolved: Removed the additional classes from init AND all whitespace around the processwire namespace declaration.

Hi all,

I'm using option 1 here for multiple sites with multiple databases: https://processwire.com/docs/more/multi-site-support/

Site 1 (the main site) works fine. When I try to log in to Site 2, I hit a blank page after login. The front end works fine. Here's the debugging info:

• Warning: Cannot modify header information - headers already sent by (output started at /home/****/public_html/site-2/init.php:138) in /home/****/public_html/wire/modules/Process/ProcessPageView.module on line 142
• Warning: session_regenerate_id(): Cannot regenerate session id - headers already sent in /home/****/public_html/wire/core/Session.php on line 874
• Warning: Cannot modify header information - headers already sent by (output started at /home/****/public_html/site-2/init.php:138) in /home/****/public_html/wire/core/Session.php on line 886

The extra lines in init are just classes, removing them doesn't change the error.

Any ideas?