I just recently purchased a used Sony home theatre receiver and am starting to set it up. I've only hooked up the left and right speakers to make sure the system works well. Sound is great once acquired but I seem to have to turn up the volume fairly high to really hear anything. Volume indicator on display starts at 0 and I have to turn it up to about 30 or so get decent volume level. I even put my ear right to the speaker as I'm turning it up so I can hear the volume increase. Is this normal or would my receiver need to be "tuned up"?