Automatic Device Output Selection.

[JNPMusic]

Hello,
I noticed over the past year that my computer will no longer select my sound output device automatically. I'm using an Apollo Twin for sound. It used to automatically select the Apollo when switched on or revert back to the internal speakers when not in use. Now every time I want to use the Apollo I have to manually select the device in system preferences. This seemed to have happen with one of the updates some time ago. Is there a way to get this to work automatically again?

Thanks.
John