Audio out of sync in Kdenlive but not when I play the video in a media player

Help
1

I am trying to edit a pretty large MKV file. Kdenlive wanted to transcode the audio and when I tried to edit without transcoding the lip sync quickly got out of sync when I started editing. So I converted the file with another program into a MP4 file with AAC audio and 5.1 multichannel. Kdenlive doesn’t ask to transcode the new file and when I play it in the media player on my PC or my phone it’s synced correctly.

However, when I try to edit the MP4 in Kdenlive it still gets out of sync when I edit. Help?

2

What is the original framerate of the MKV file? Maybe variable framerate as you mentioned playing on phone. Such files must be transcoded by Kdenlive otherwise audio get out of sync on Kdenlive.

What is the framerate of the converted MP4?