Audio corruption with opus

[atohmdiy]

I am using CachyOS and install av1an from AUR.

If i set av1an to also encode audio in opus, i found out that the audio end-up being kind of corrupted. There is random section of the video with no audio at all.
Now when i am doing an av1en video encode, i encode the audio with ffmpeg and remux with mkvtoolnix.

My opus settings are the same as ffmpeg :
libopus -af channelmap=channel_layout=stereo/5.1/7.1 -ar 48000 -b:a 256k

[atohmdiy]

I can also confirm that audio corruption occur with defaut (-copy) option.