"It seems the amount of Spanish viewers has gone up lately." -Fraser
From Part 5 of Minecraft Awesome Expedition, Fraser recalls how user luisbuceta would say "Jajajaja" whenever Fraser acknowledged him. His first impression was that the person was being a dick, but realised soon after that he was just Spanish. Jajajaja is now occasionally used by The Chat to further troll Fraser's failures.
Jajajaja is a form of laughter used by some Spanish players (similar to a "lol"), as the J is pronounced like an H in Spanish. Whenever Fraser or Becky say it, though, they always ignore the Spanish pronunciation, so they pronounce it like it's spelled.