From Halopedia, the Halo wiki
He then moved to the United States and, in July 2011, began working with 343 Industries on Halo 4, along with composer Neil Davidge. However, contrary to Davidge, Jinnouchi is an integral part of the studio's audio team. He composed several tracks for Halo 4: only one of his tracks was featured in Volume 1 of the Halo 4: Original Soundtrack, but nine were present in Volume 2. He also composed the music featured in the Halo Xbox One E3 announcement trailer, and went on to compose most of the Halo 5: Guardians soundtrack.