You can file this under "Problems you didn't know you had":

Mid-speech, however, the HD turned on Obama, exposing a small collection of saliva in the left crease of the candidate's mouth. The development nearly incapacitated my housemate; he spent the remainder of the speech in a nervous fit, wishing aloud that one polite delegate would flag down the candidate and discretely wipe his own mouth, the telltale indication that Obama "has got something - right over- no -a little to the left - there, you've got it."

And here I thought that HD was mostly going to be of interest to sports fans and action movie fans :)