Software :: Final Cut Express Audio - Cannot Hear Music & Sound Track On The Film Clip

I have Final Cut Express 4 running on an iMac with Leopard 10.3.5. The problem I have is I cannot hear a music track & the sound track on the film clip at the same time when I run the clip. I only hear the clip sound track until it finishes then the music track plays. If I drag the scrubber bar along the time line I can hear both the music & the Clip sound track together. This only happens when I logon to the Mac as an Administrator. (I have never managed to hear both sound tracks together whilst logged on as Administrator.)

In desperation I created a user account on my iMac. If I logon as a user Final Cut Express 4 works ok ? I hear both sound tracks together when I play the clip. Any ideas how I can make the Administrator account work as the User account does? As the iMac is only used by myself I don?t need any user accounts.