No sound while using mono channel

im coding webms using the libvpx-vp9 codec, I always used vorbis for the audio codec and everything was fine, but when I change channels from 2 (stereo) to 1 (mono) I dont get any sound.
I also tried to use the audio codec opus, but i dont get any sound at all.
Any suggestions?

You can select the default for format option for the audio codec and you’ll be able to export to mono or stereo.


When i use WebM and pick the mono channel and make a video, I have audio, but when I use WebM VP9, and pic the same options and make a video, it doesnt have any audio, do you know why?

No I do not. The webmVP9 export with default settings exports both mono and stereo audio here.


The “WebM” preset uses vorbis audio. The “WebM VP9” preset uses opus audio.

When I try to export using vorbis and one audio channel, I see this error in the export log:

[vorbis @ 0x7f0e301849c0] Current FFmpeg Vorbis encoder only supports 2 channels.

So it looks that only stereo is supported if you use the “WebM” preset - unless you change the audio codec to something that supports mono.