M-audio Audiophile 2496 On G4 933mhz W/garageband, Throwing in the towel, fighting too long Options

[The_Apparition]

I have been trying to resolve this issue for well over a year (with Gband1 and still with GBand2) and am finally throwing in the towel...

Equipment: A 933MHz G4 1.5Meg RAM with GBand2 using MIDI-OUT on a Yamaha Clavinova CLP-115 into an M-Audio Audiophile 2496 (A2496) MIDI-IN, with latest driver 1.7. OS 10.3.7 and GBand2 on internal 7200RPM Drive recording onto a separate, cleanly formatted internal 7200RPM Drive.

Issue:
1) Playback of GBand2 recordings when output through the Audio Out of the A2496 produces pops and clicks.
2) Playback of GBand2 recordings when output through the Internal Audio is sluggish.

Things Tried:
1) Followed Electronic Musician (or Keyboard - don't remember which) magazine's article on streamlining Panther to no effect.
2) Killed processes that don't need to be running, Retrospect Backup, iTunes Help, etc.
3) Ran shadow killer to reduce load on screen updates, removed fonts, etc.

Any ideas / suggestions? Any experience on latency issues, clock syncing, etc.?

Thanks in advance.