Like they say, they've had boards which have been inundated with adverts and spammers and the like when they gave all users the ability to put iframe code in.
I have asked them if they can integrate it into the Youtube button, but as Audioboom is probably not that successful I dunno whether they'll give it the time.
For now I'll just keep an eye out for when you lot put links in & if it's got iframe stuff I'll change it for you.