Single pop when turning
 

I'm getting a single fairly loud pop when turning the steering wheel while stationary or at very low speed, only before driving on first start-up. Any thoughts on where to start looking? Probably going to replace the steering stabilizer next time I'm under there, hopefully I will have some time to diagnose then... A cursory search turned up nothing that matched my description. 70k mile 2005 limited 6MT roadster.