Client Socket.io reconnects all the time to websocket

I am connected via Socket.io 1.3.4 (via websockets) to the NodeJS server and client socket.io fires up "disconnect" event 5-30 seconds.

Every "disconnect"->"reconnecting"->"reconnect" iteration takes approx. 2 seconds. I am connected via cable to pretty stable network. Server is hosted on AWS.

Sometimes I have bad Wi-Fi connection, but no "disconnect" event fire up at all.

1. 
   

   How can I debug this issue?

   
   


2. 
   

   How can I see who is guilty - server or client?

   
   


3. 
   

   How does socket.io understands that it is time to disconnect? Could not understand this from their code.