Question Kunena Module positions only display when logged in

Having a bit of a problem, but I have searched the board and not sure what is going on. I have placed some ad modules in the Kunena Module positions but have noticed that these only display when the viewer is logged in.
I have checked and the modules are all set to public so I am not sure what exactly is happening...
any ideas?

Thanks.

EDIT: Just a bit more info. Joomla version 1.5.9, Kunena 1.0.8.
When security settings are set as:
Registered Users Only = No
and
Public Read/Write = No
modules in Kunena module positions (Kunena_msg_1, Kunena_bottom, etc.) do not display if the viewer is not logged in.

When security settings are set as:
Registered Users Only = No
and
Public Read/Write = Yes

modules in Kunena module positions (Kunena_msg_1, Kunena_bottom, etc.) do display even if the viewer is not logged in. Unfortunately this is no good as I need the forum to be limited to posts by registered members.

Thanks.

Can't confirm this.

Tested it on a local server and every modulposition in Kunena is visible to guests.

Joomla 1.5.9, Kunena 1.0.8.

Kunena-Security Settings
Registered Users Only "No"
Public Read/Write "No"

tested with:
Module Type: mod_banners
Show Title: no
Enabled: yes
Position: kunena_profilebox / kunena_bottom / kunena_msg_1
Access Level: public
Menus: all or
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