Since SignalRGB app service is not worldwide available, the use of a proxy service is often needed. However, this software does not follow the system proxy settings, nor does it have a dedicated proxy setting. (That’s partly the reason why there are so many posts about “fail to login/download”)
In this case for the app to function properly, a system-wide virtual network interface is needed, which is inconvenient and takes too much CPU resource. This method also affects other softwares in the system with different network configurations.
So what I would suggest is to add a proxy setting to SignalRGB app, or make it follow the system proxy setting.