Sound problem when running multiple programs

Hello, I have this little pet peeve of mine. Whenever I am using cubase, with Youtube (trying to follow tutorials), or opening a notation program with Finale 2011, I am always unable to hear sound from the later programs and vice versa because it has sound.

It is a little annoying cause when I save a file from cubase, it immediately opens Wavelab and I have to close everything, and open up wave lab by itself in order for the sound to work. I know my way around it but just curious if anyone know a solution to this so I can hear multiple program sounds then just from one program. Thanks.

check release drivers in background.