No audio on lower tracks

I have just started a job finishing up the post editing on a client's system. g5 , fcp 4.5, the dsr-11 is not turned on, so the audio is straight from mac. The audio on a1, a2 plays fine but audio on a3 a4 does not come through the speakers. I can see the levels on the meter.
I tried trashing preferences and fixing permissions. I looked at the preferences and I think that they are fine. What am I missing?
Thanks for any help,
George McMorrow

Did you do a 'Audio Mixdown'?

In your FCP User Prefs, how many real time audio mixing tracks are shown, should be 8.

--ken

Hi Ken,
Thanks for the quick reply. It does have 8 in prefs for audio. The only thing that I was worried about was the amount of free space on the fw drive. It is 250 gig with only 13 gig available. I know that this is not much, but would this cause a problem with the audio.
George

George,

Your media drive is too full, but this would cause dropped frames and not the loss of two audio tracks.

Did you try the audio mixdown?

Very far left on the timeline, be sure that the little green speaker icons are turned on for audio 3 & 4.

--ken

Ken,
The green light is on the speaker icon. If I drag the audio up to the top level, it plays. I did notice that the fcp is 4.5, not 4.5.x. I did turn on the audio mixer, but to no avail. I will transfer the media to a bigger drive when it arrives, and take a dupe fw drive back to my office to see what it does on my system. It is just an annoying glitch that you hate to start off a edit session with. I guess that I am glad in a way that it wasn't something obviously simple that I missed, at least not yet.
Thanks again for your time,
George