Hello,
I have tested it and I am able to access all 8 panes. Isn't there any other web part or javascript linked on that template/page which could be in conflict with the accordion? Could you please create a blank page without any content and even without the master page inherited and place the accordion there? By this approach you find out if there is a problem with the accordion or with some other part of the original page.
Best regards,
Jan Hermann