Sync, Corruption, Clicks and Pops

Hello All,
So I'm having multiple issues with my setup here as I'm preparing to go into a big film score and don't want to have these headaches once I start.
First problem, and this might be the easiest to solve, is when playing back I'm getting intermittent clicks, pops, distortions from my sampled instruments. I'm running about 7 - 8 instances of Vienna Instruments, about 12 instances of exs with various samples/old Vienna Library, two instances of Stylus RMX, two instances of StormDrum (2-3 patches each) and one instance of Ethno. In addition to this I'm running my giga setup via lightpipe, and a Roland 5080 via Midi. I'm also running the movie, full length and DV quicktime format. I have all my audio samples on one external firewire Glyph Drive, the video on another external firewire Glyph drive, and the project on an internal (separate from the System Drive) hard drive.
My initial idea was that these clicks and pops might be caused by a bottleneck on the sample drive. This drive I believe is running firwire 400. Are the amount of Samples I'm running too much for this drive? Would it help if I upgraded to firewire 800 or maybe got another internal drive running 10,000 rpms? Should I re-encode my movie so its not so hard on the drive bus but more processor intensive?
My other idea was that it might be a case of bad Ram. Checking Logics System Performance window, I was only showing 75% on one processor and 30% on the second processor. So I opened up the activity monitor to check out how much ram was being used and it showed only 3.17 gigs of ram used. Going back to Logic all pandemonium broke loose with my project.
Which brings me to my second problem...this project is having crazy sync sample rate issues. Everything is distorted and garbled being played back, Logic is returning an error sign saying that I'm not synced and showing a random sample rate (4168). Restarting my system and all the usual stuff (repairing disk permissions) helps not at all. Everything still sounds messed up. Removing the movie from the project lessens the distortion but the same sync error turns up. Opening up other projects, I don't run into these problems. I even opened the Autoload of this project and I didn't have this problem (other than the already mentioned clicks and pops).
Is this project corrupted beyond retrieval? Do I have to manually copy everything to another project? Why did opening the Activity Monitor set this off?
If you read through this long post and know any of these answers that would be awesome.
Here's the specs on my setup.
Dual 2Ghz G5
4 GB DDR SDRAM (8 x 12)
ATI Radeon 9600 Pro
2 Glyph Drives
Audio Sample Drive - 400mb/sec
Video Drive - 800mb/sec
Motu PCI - 2408 mk3
GigaStudio PC
Roland 5080
TC Powercore
Everything slaved to an Apogee Big Ben at 48.
Thanks!
Oh yeah Logic 7.2.1.
Dual 2GHZ G5   Mac OS X (10.4.7)  
G4 1.25 MDD   Mac OS X (10.4.3)  

Hi,maybe this can help:
In addition to this I'm running my giga setup via lightpipe,
Going into what? Logic Pro thru the Motu 2408? into a digital mixer?It is not clear how you route this.If the Motu is the clock master,and you route everything through it,you should slave the Giga playback card to it,and make sure the Giga card can and is synced properly.
My initial idea was that these clicks and pops might
be caused by a bottleneck on the sample drive.
Nope,highly unlikely. A bottleneck on a drive will only slow down a system.Unless you are using certain western Digital drives that shield their power and their FW grounds together...then the hum from the drive spining would be what you hear.
My other idea was that it might be a case of bad Ram.
Nope,highly unlikely either...you would simply have more crashes,and freezes.
Which brings me to my second problem...this project
is having crazy sync sample rate issues. Everything
is distorted and garbled being played back, Logic is
returning an error sign saying that I'm not synced
and showing a random sample rate (4168).
Sounds like you are not slaving the word clock correctly somewhere int he chain...but without knowing what sound card the Gigastudio is using,and how you have your word clock distributed,I can only offer the following:
Remember to make ONE and only ONE device the sample rate clock master,and slave the rest to it.
Please try to re-connect your word clock cables...and maybe even start by running only one device at a time,until you find the one that causes the problem.It might be a headache at first,but the only real way to troubleshoot this stuff is to go one by one piece of gear and find the bad one.Sometimes a bad word clock cable,bad power cord,bad grounding between devices,can cause all sorts of problems,including clocking issues.
i hope this helps,
Nick

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    Old Today, 05:17 PM #1
    USCRash
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    Posts: 12
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