Pops and ASIO Time Overload

Hello all
I need some advice. I’m usually pretty good with this stuff but this has me baffled. I run a pretty big orchestral template on my rig (about 45 tracks or so). The template isn’t as crazy as I’ve seen some folks but it has quite a few tracks.

Ever since I added EWQL Hollywood Brass to my template the audio performance has gotten even worse. I’ve raised the buffer in my Apogge Duet to 1024 during playback but I still get the pops and clicks when I have a lot of tracks playing, especially when the HWB tracks get involved.
I took the following numbers from a session I had running 41 tracks and about 20 plugs.

Host Macine:
Computer: MacPro1,1 (2006) Snow Leopard OSX 10.6.8
Processor Speed: 2.66 GHz
Number Of Processors: 2
Total Number Of Cores: 8
L2 Cache (per processor): 8 MB
Memory: 24 GB
Bus Speed: 1.33 GHz
Audio interface – Apogge Duet Firewire
DAW – Cubase 6.0.5

Slave Machine (networked by VE Pro)
Cunstom PC Intel Core2 Quad Q9550 @ 2.83 GHz
Windows 7 Ultimate 64 Bit

3 x Vienna Ensemble Pro networked to PC slave
VE Pro 1 – 11 channels
VE Pro 2 – 8 channels
VE Pro 3 – 7 channels
4 x EWQL Play running on host machine
Play 1 – 11 Hollywood Brass Channels
Play 2 – 11 Hollywood Brass Channels
Play 3 - 11 Hollywood Brass Channels
Play 4 – 3 Storm Drum 2 Channels
2 x WIVI Instances on host machine
1 x Kontact Instance on host machine w/ 3 active channels

The CPU meter on my Mac at the height of the project shows 30% used 17% system and 54% idle. The memory usage shows 8 GB free, 1.10 GB wired, 4 GB active, 10 GB inactive and 15 GB used. The ASIO meter in Cubase is going nuts though and shows ASIO time overload and of course the audio is popping and cracking.

What do you guys think? Where might the problem be (Cubase, EWQL Play, Mac Pro, Duet, hard drives)? What would the solution be (Solid State/faster Hard Drive, new audio interface, update OS, new computer)?

Your insight is welcome and appreciated.