1. A method for determining pitch lag for a current frame of information in a long term prediction (LTP) encoding system, the method comprising: selecting a lag search window for the current frame in a vicinity of a previous frame pitch lag, the lag search window having an upper boundary and a lower boundary; calculating, by a processor associated with the LTP encoding system, a pitch lag estimate in the lag search window for the current frame; determining if the pitch lag estimate is unreliable based in part on an average cross-correlation for a plurality of previous frames; and upon determination of the pitch lag estimate to be unreliable, selecting a new lag search window and calculating a new pitch lag estimate in the new lag search window.