WP 2.6 RSS2 XML parse error

Greetings,

I am running WP 2.6 on several domains. I updated several days ago.

One site the blog feed and the comments feed work with no problems.
https://www.flyboyjon.com/blog/feed/ and https://www.flyboyjon.com/blog/comments/feed/

On another site nether are working.
https://www.steamfaire.com/ops/feed/ and https://www.steamfaire.com/ops/comments/feed/

On the third site the entries feed fails but the comments feed is fine
https://www.wanzeraviation.com/airship/feed/ and https://www.wanzeraviation.com/airship/comments/feed/

I checked all of the PHP files for spaces and tabs outside the PHP tags. Lots of spaces, no tabs. Removed them all and uploaded the files. The problem still persists.

The error is:

XML Parsing Error: XML or text declaration not at start of entity
Location: https://www.wanzeraviation.com/airship/feed/
Line Number 2, Column 1:<?xml version=”1.0″ encoding=”UTF-8″?>
^