I'm doing a multiplayer with a friend. I was near a cave when I heard the usual wind and creepy sounds you hear in the game. But I picked up a word. I realised that there was a voice but all I heard was 'You'. I freaked out and got off the game. I went back on it later that night and I was hiding in my hut (near the same cave, but not enough that I can see it) and I heard what sounded like a child's whine, before it deepened and turned to a creepy, glitchy, evil gurgle. I got off it straight away and my friend hasn't heard it. EDIT: I can't find any answers anywhere. Also we are using the OZOcraft resource pack, could that be the answer?
This is caused by your resource pack "OzoCraft"
A quick google search comes up that yes, "OzoCraft" Resource pack adds sounds that can be described "voices". I spent some time and downloaded the resource pack, and looked through it's audio files. It is indeed the ambient cave sounds, precisely 2 to 6.