Logic Delta / Audiophile 2496, Logic crashes on Quit, general problems with Audiophile Options

G4/466, OS 9.1, 384 MB RAM, Logic Delta 4.6.2 (dedicated 40MB RAM), M-Audio Delta Audiophile 2496, latest beta drivers (v1.5.6b)

I am able to select the ASIO driver in hardware preferences, however if I try to record I get an 'ASIO hardware malfunction error -999' whether I select the analog or the S/PDIF source. While the rest of the app seems to work after that, when I quit Logic hangs up without any error message (mouse pointer is not frozen though), requiring a hard reboot.

Generally, I haven't been very successful to get the Audiophile to work AT ALL... Their drivers (especially the Control Panel) is a nightmare, preferences don't stick, the sound (through Sound Manager) is mostly awful and distorted. But I couldn't find out any pattern what causes the Audiophile work sometimes and what doesn't, it just looks like it has its 'moods' on its own.
I have reinstalled the card and the drivers many times, trashing prefs, to no avail.

This week I took it back to the store, they installed the Audiophile on their G4/400 (OS 9.1) and suprisingly (well, not really as a G4/400 is *not* the same as a G4/466, unfortunately) they were able to make the card's analog I/O work with MicroLogic 4.7.3 even by using the original beta driver and the ASIO driver that comes on the CD.
But then I have demonstrated the problems using the card with Sound Manager, and the symptoms were the same as on my G4, i.e. clicks, noises and a kind of short 'fade-in' effect if you play *any* sound. Finally, after my demonstration their Logic started to crash on launch with error 3 (illegal instruction), freezing the G4.
Nevertheless, the guys in the store tell me that the card *itself* appears to be working (which it actually really did, at least for a while) and therefore they can't take it back.

Has anybody ever been successful in using the Audiophile with a G4 (133 MHz bus)? If so, what's your secret?

Thanks for any help or advice