When i try the demo and i open my webcam or i stream a video
sometimes it shows hd but sometimes it shows very pixelated video frames
my question is do you guys use a cheap server for the demo
or what can cause this problem?
Whether or not the media server is cheap or not has little to do with he video quality.
The online demo of AVChat gets a lot of usage so we're conservative with the encoding settings used.
If you could attach a screenshot showing the pixelated image we could indicate the exact issue. Did you experience pixelated frames in your own video preview (top left image) or when viewing other people in the chat or yourself?
This article goes in detail about what needs to happen for everyone to have good video quality.