Are you talking about using them for music listening or HT. The post is in the HT area, but you mention 5 channel stereo?
What receiver do you have? If it is a Denon, the levels will be set differently depending if your in direct mode, 5 channel stereo, dolby digital, etc... If you hit the circle button on the remote, it will cycle through each speaker and show what the auto setup has for each speaker.
of course that is if you have a Denon
For HT, you will not always hear stuff out of the surrounds, but when you do, you will know they are there. On my Denon in 5 or 7 channel stereo mode, things sound great. When listening to a DVD Music disc in 6.1, it is awesome.
Sorry I can't be much more help.
