I'm not sure what the "official" term is but I will try to explain.
When my ST and LOTR are in attract mode and I hit one of the flipper buttons I get a random sound. For example in ST I get " Welkom to the USS Enterpise.." or in Lotr I get " Shireeeee .. Bagginsss..
I don't get it when I hit the flipper buttons of IM or AV. Is this a setting that I need to activate or does these pins don't have it ?