Trainspotter

Back when club DJs used vinyl and didn't have their beatmatching done for them, a trainspotter was a person who focused on the transitions between records, just waiting for a trainwreck, i.e., mixing in a record that is off tempo, creating a discordant, galloping effect between the two drum tracks. (This effect could be quickly overcome by the DJ, if the DJ was competent, and most of the crowd would not have noticed, thus the need to be actively looking (listening) for it.)
The word can also apply to watching for anyone to mess up anything.

Because Eric Prydz plays on CDJs and has a computer beat match for him, it's completely pointless to be a trainspotter at his show.
-OR-
So you just watched your friends destroy their lives? You're such a trainspotter.

1👍 1👎