Mausoleum Suite
From Halopedia, the Halo wiki
Mausoleum Suite is a suite of songs included in the Halo 2: Original Soundtrack. It includes Destroyer's Invocation, Falling Up, Infected, and Shudder.
It runs for 8:10.
Hidden Message
When the track is played backwards, a hidden message can be heard. At normal speed it is inaudible, but sounds similar to the Gravemind's voice. However, when sped up words can be heard and the voice begin's to sound like that of a prophet. It is more likely that it is 032 Mendicant Bias. Whether either is the owner of the mysterious voice, or something/someone else is debatable.[1]
