I'm working on a video call application using webRTC. I use this application only in the local network. In testing several connection devices that were made successfully connected very well. However, there are some devices that I don't know why they can't make calls to some devices. And it's behaviour was so strange. Here is a call simulation that I did :
*All devices connected to same local network/wifi,
** The problematic device in Bold
Here's the screenshot that I get from chrome://webrtc-internals/
The connection state on problematic device
The state is still on new state, not changing



I'm using Stun server from google, I have also tried without using iceServers. The result still same. I think if we are only in the local network we don't need a stun/turn server right?
strangely the problematic device cannot make outgoing calls to other desktops, but can make/receive calls with the mobile. And between problematic devices also cannot be connected because in my opinion the problem is that the problematic device cannot make outgoing calls.
What I am confused about is what causes some devices to be unable to make outgoing calls like the case above? I believe this is not a fault in the code, because the call runs flawlessly on other normal device. I have tried various ways, until I use Perfect Negotiation Logic at this time, but the result is still the same.
maybe someone has experienced something similar, can provide a solution in the case above. So much appriciate from me