[Swan217]

Originally Posted by dlavery

The referees had all worked for the week before the event to develop a set of very visible hand signals to correspond to the common violations. They also all had whistles. During a match, if a violation occured they would blow their whistle as they threw the penalty flag, and use the hand signal to indicate the violation (agressive play, human player outside the loading box, robot not in loading zone, etc.).
-dave

Originally Posted by Rule 7.4

No loud music, audio systems, whistles, banging sticks, blow horns, etc.
They interfere with announcements. They prevent teams from hearing
important announcements, can be annoying, and can cause hearing loss.
Power may be shut off and/or radio/cd player, noise makers confiscated.

Looks like the referees were in violation of Rule 7.4. They should have had those whistles confiscated by the proper authorities.