Just set up my Rift yesterday, had a blast myself as well as having a blast demoing it for family members!
However, when having my brother try out Robo Recall, I noticed that the left Oculus Touch controller vibration was significantly louder than the right one. I didn't notice it before when playing myself, and neither did he notice when playing. It seems like the game audio covers it up, but now that I know it's going on, it's hard not to notice it even while in any menu/game. It seems to feel the same as the right controller, it's just as though it's vibrating something that may be slightly loose and causing extra buzzing, like a spring. I've replaced the in-box batteries with fresh ones, and tested the controllers without the battery cover on in case those were contributing to the issue, but it didn't seem to take care of it completely (although putting slight pressure on the bottom side of the battery somewhat diminished it).
I've done some googling and saw some hits about similar issues in the Oculus subreddit and Oculus' main forums, but it doesn't sound like there is a clear explanation or resolution for it. Perhaps I'm being nitpicky and fussy about it.
Anyways, just checking to see if there are any other similar experiences from you all, or maybe something I've missed as far as what is typically done (or perhaps not done, since it's only kind of a minor annoyance/concern) about this issue. Thanks!