"A captain needs to set an example and it's not acceptable for any player, let along a captain, to show dissent at an umpire's decision, " match referee Roshan Mahanama commented.
"It is also worthwhile to mention that at no stage had I indicated to the England team management that the third umpire had forgotten to adjust the volume of the speakers, " added Mahanama.
Following the incident, an official investigation was conducted in conjunction with Sri Lankan match referee Roshan Mahanama, when it was discovered that Harper had his speaker turned up to level four out of 10.