CCF profiles (solid lines) of X Sgr (left) and BG Cru (right) observed at the same phase during different epochs and their respective Gaussian fit (dashed lines). Cycle-dependent line splitting patterns cause systematic error for RVs derived via fitting Gaussians (Anderson 2013). This phenomenon is much stronger in X Sgr where the systematic error between the two epochs is clearly more discernible than in BG Cru.