As a 10-year "veteran" in the DJ/KJ business, I have to say that while a static on-screen ad probably does no harm, it is not the best option. Perhaps the biggest reason we are out there (other than to push buttons
) is to provide interaction with the patrons, whether that be entertainment, or, in this case, information. I regularly work in announcements for happy hours, upcoming events, door prizes, etc., while bringing up a singer or going into a dance/music portion of a show...without skipping a beat or having a singer waiting while I do so. Maybe a static ad flashed occasionally while playing some dj music especially if you have a background graphics program running on monitors or bigscreen would be good.