You should not have problem if you only use
Lua Code:
d(...)
CHAT_SYSTEM:AddMessage(message)
CHAT_SYSTEM.primaryContainer:OnChatEvent(nil, displayedMessage, category)
And with the third, you already broke certain addons which enable multi containers.
And for your problem, it's because with pChat, I enable system messages per default in every tab. (it was enable in every tab or disable everywhere).
you can simply uncheck system message by unchecking in tab options the "system" entry (added by pchat).
You can see more detailled explanations here
http://www.esoui.com/downloads/filei...ge=11#comments (and in page 13).