In my line of work, we have a built in way to cover it up...we shout 'objection' and then glare at the opposing counsel. This usually shakes the judge from his daydreams as well, and he shouts sustained. All this commotion wakes the jury, and while they have no idea what is happening, they see everybody glaring at the other lawyer and assume he did something wrong. (thats what he gets for clearing his throat).