Not really. 1390 comes to mind. If you can look at the settings in the BT router, perhaps they have set a particular MTU and perhaps you could copy that. Otherwise, just lower it by a 100 and experiment with speed until it levels out. If that does not help, it could also be duplex and speed settings. The modem might be hard coded and you are using auto negotiate. Again, I would check the settings on the provided router if possible to get an idea of what you need to setup.