I have noticed that OBiApp on PC only captures IP addresses when it is started up, not when you login. If VPN is running and then you disconnect, it will not have the correct IP address to try. So even if you logout and then log back in, you will not get connection and get a 408 error.
Frankly, I am going through major issues trying to use my Obion app. First, my ISP screws with VoIP traffic. Second, I've found that I need to try to setup some type of VPN to get around this. All this effort just to use my dang Obion app. Now of course if Obihai would both secure the app via SSL and/or securely connect us via SSL on the Obion I wouldn't have all these hurdles :D