Time synchronization

I’m experiencing a Time synchronization issue in RTMaps while fusing Camera, LiDAR, Bounding Boxes, and ClassID data. The Bounding Boxes, and ClassID timestamps are synchronized as they from same GT Camera, but the LiDAR timestamps consistently differ by approximately 450–700 ms. I have set the synchronization tolerance to 700 ms but yet the overlay is not good. Could this be due to different timestamp sources/clocks, or is there another synchronizer setting that I should check?