Well, 1-6-1 says:
Communication devices, other than audio recorder, Local Area
Network (LAN) phones and/or headsets, including but not limited to mobile phones,
still photograph(s), film, analog or digital video(s) and/or Internet depictions, shall
not be used for coaching purposes during the game or between periods.
Is this a "communication device"? Maybe, but it certainly isn't the type of thing this rule was meant to prevent. This is supposed to prevent using cameras/printouts during the game, having radios in player headsets, etc.
If it doesn't sound like an official's whistle, and he's not doing it to distract the other team's signals, I would leave it alone.