Marcoholo59: Accepting a game invite whilst playing a round - Goes straight into Head to head and not the game that I have been invited to
I find this happens when I am being invited to a game, sometimes when I accept, the screen shows me VS the person inviting me....If I wait till it finishes loading, it does go to the game. It seems, when one of the invitees is "spinning" and you go to join, this is what the screen looks like (it looks like a head to head match when it is not). So, when you are cancelling, you are in fact "bailing" out of the game you were trying to join.
Next time it happens, try letting it play out rather than hit cancel.
Good Luck... I do think the beverage is worth having in case I am wrong.