Flashing mute buttons on track mixer

I have opened one of my previous projects and when I
try to play it back, some of the tracks will not
play, these tracks have flashing mute buttons in the
mixer, why is this, and how can I get the sound back
on the tracks?

No its something more serious that I can't figure out, nearly all the mute buttons are flashing, when I click them they turn blue, but then when I click them again they are still flashing, tried solo mode then unsoloing , and muting unmuting tracks but still the same problem, please help!!!

17" Macbook Pro Mac OS X (10.4.4) logic Pro 7.2.3, Live 6, Novation 25SL, NI plugins

It really sounds like you have something solo'ed
somewhere... it might be a track that's not visible
in your track mixer.

Try soloing any track, then un-solo it by
option-clicking on the track solo button. That
should clear it.

yep cheers thats got it