BB - go to the top of a page. Just below where it says "Mudcat Cafe" there is a line of clickies starting with "Lyrics & Knowledge" and finishing with "Help". If you click the one that says "Membership" it takes you to a page, which if you are logged in as a member contains a number of boxes with your details. Below all of these are (currently) three extra option choices.
One says "BS Filter" - if the YES button is selected, when you look at the forum, it hides all the contents of the BS section. It sounds as if you have this one selected.
Another button says "Mix Music & Non-music". If this is YES all threads are listed together regardless of whether they are "BS" or not. If you choose NO the BS appears as a separate section below the "serious" section.
Of course. if you have already ticked the do not show BS, then the second button doesn't have any BS to mix in with the serious stuff.
NOTE - the BS filters only work if you are a member and logged in. If you are a guest, the BS is by default there as a separate section.
Quack!
GtD.