CKEditor displays entire site page when rich text is switched on The ckeditor is switched off by default. If there is no text present in the field while editing, the cck provides a wysiwyg interface with no text present when rich text is toggled on. However if any text is present and Rich Text editor is switched on then a particular page of the site gets rendered instead of the text. On switching off rich text the rendered page html gets displayed.  Please help.

CKEditor version is latest(7.x-1.13)
The issue was due to a php code used in the donate button of the same page which got rendered in all wysiwyg fields. There was error in the code which disallowed the search to function properly. I was able to identify the issue using elysia cron which displayed errors  when search cron was running. Checking the logs helped me resolve the issue. 
Error in one page could cause the CKEditor to display the same page for all wysiwyg fields when switching on rich text is interesting. Thanks.