Issue Description

I try to use rs::config with rs2::pipeline to record and read bag file according to the example codes here : https://github.com/IntelRealSense/librealsense/blob/master/src/media/readme.md. Record process works well and it can generate bag file which can be loaded by realsense-reviewer. However, when I try to read bag file with pipeline, pipe.poll_for_frames(&frames) always return false.

Does anyone have a clue about this problem? Thanks.