If you are experiencing obscure problems with asio

[Zer]

you might want to try setting the colour depth to 16 Bit instead of 32. In some cases the graphic card could be the issue for buffer problems and things like that:
http://www.gearslutz.com/board/3915329-post14.html

[Zer]

sometimes alternate drivers may help, too: http://www.omegadrivers.net/
(but it seems that the project is somewhat deserted).