Strangeest Logic Problem Ever, Won't play audio tracks in Platinum Options

[Ryanair]

This is the most bizzarre logic/mac problem ever, i've got a new mac G4 800 with 1.5Gig Ram, mac os9.2, delta-66 card/omni I/O, a midisprot 4x4 and AMT8. Everything was working perfectly for about 3 weeks, then i updated the drivers for the delta card to try and stop the errors i got upon booting logic, since then in logic platinum, if i start the program,(even without any preferences/autoload) and i import an audio file (any type) then drag and drop it onto the arrange, and start the sequencer, the audio files don't play at all, i don't even get a flicker on the level meter, it's like they're not even there! BUT if i double click on the audio file in the arrange window to see the waveform, and use the speaker button, it plays no problem, and i get a level reading on the mixer page/boarder of the arrange window. This problem is the same with Mac AV and the delta Asio.
I can record audio perfectly. (And the audio instruments, eg, EXS work fine.
If i start uplogic and record audio, then it plays back fine, but as soon as i import an audio file or bounce etc, the audio in the sequence will no longer play.

HOWEVER....

I've tryed a friends Logic Gold on my system, and everything works perfectly, it now seems to be just logic platinum,
but remember, everything was working fine when i first got the system,
Please can somebody help me, thanks.

[TalonFFL3]

im stuck with logic too, you look down a few posts and youll see my problems
im startin to think maybe we should both switch to something else and not even apple could save this crap software from its ubiquitous bugs