In case anyone with Be* isn't aware, you can now change your line profile via your member centre - on login scroll down and it's bottom-right:
1) optimise for speed = 3db profile
2) standard setting = 6db profile
3) optimise for reliability = 9db profile
4) gaming mode on/off = fastpath
Nice!
edit: it's available for all account types, apparently there is a known bug that some members may not have it yet.