My iPhone is always in silent mode, but this also prevents Avelon from playing videos with sound. I guess playing sound should be independent of the ringtone silent mode.
But I really like it that there even is the possibility to watch videos in the app, I guess that’s the first app supporting it.
The video does play with sound, when the iPhone mute switch (on top of the volume buttons) is toggled to off. My iPhone is always muted, I don’t like notification sounds.
The videos were uploaded by me to pixelfed, and so had sound as soon as I unmuted my phone.