Not sure if anyone else is hearing this..at first I thought it was part of the game but then I realized it was very annoying and was a little to repetitive to be on purpose. The sound I'm hearing is basically a thump thump thump sound...like a paint bucket hitting your house...and it'll reoccur every 5 to 8 seconds...even during cut scenes and the volume of that particular sound is louder than other sounds. If I Alt+tab out and back it seems to go away for a while.
Just putting it out there so hopefully they'll consider looking into that and other weird sound issues (like sound cutting in and out if you move around inside..or move outside to inside).