Help with misaligned sort indicators

Hi,

I'm not sure how to debug this problem. I would greatly appreciate any advice pointing me in the right direction.

I'm on Mac OS X 10.9.3 with Ruby 2.1.2, Rails 4.1.4, and jquery-datatables-rails (2.1.10.0.2). The sort indicators at the top of the columns on my tables are misaligned. This must have happened within the past few days. Here is an example,

Note: I've zoomed up the image for clarity.

Thank you for any assistance.