Video play only on browser not in any other player but Vp9 helps but still has problem

[iamappmaker]

I am recording a canvas in webm and converting it to MP4 using android MP4 transcoder. I tried all mimeType but video get converted only 1 second. Only VP9 works in VLC, google photos and few other player but it cannot be converted to MP4. It gets error after converting few frames and output is less than 1 second. I tried { mimeType : 'video/webm',
recorderType: WhammyRecorder }

This works in player as wells converting to MP4 without any error. It won't record audio.

I have completed my project but more than a month i am struggling to save MP4.. Please help

Which suggest me best mimeType, recorderType and other configuration to use.

This is app supposed to work in Android 6 and above so i like to know WhammyRecorder has any problem and it will working in all android chrome browser .