sice vegas 4, sometimes i have this problem. on ptt, the audio gets some "tic" tic".

the audio on timeline are ok. the rendered w64 are ok. disks, directx, cables camera (tested with others softwares, all working fine) but only vegas has problem on ptt. using 5b now. same thing. audio gets tic tic in some parts. ppt only the that part , same thing. if i render the video in one avi, and ptt only it works, but in the project (1:30) the problems back.

any tips?