The timestamp of whisper is not very accurate.
The following is the comparison between Microsoft Cognitive Services Speech and whisper.
1
00:00:00,120 --> 00:00:01,379 (Microsoft)
[00:00:00.000 --> 00:00:02.000] (whisper)
2
00:00:02,120 --> 00:00:06,320 (Microsoft)
[00:00:02.000 --> 00:00:07.500] (whisper)