Hi everbody,

I have a weird issue that I can't get my head around.

I am using a FF UC (fw 115, driver 1.63) hooked up to a MBP 2.66C2D (OSX 10.6.8, 4GB RAM, SSD) to interface Waves MultiRack with a 01v96v2 VCM via ADAT I/O. Also, I am clocking the desk at 48kHz via Wordclock from the FF UC (with a proper 75Ohms cable, 40cm long). To stay within a really comfortable CPU load for the Mac, I run this at 128 samples of buffer.

All the indicators tell me that all is running fine, however I am hearing occasional clicks in the audio. They sound like "typical" sync/clocking ticks, and they have seemingly nothing to do with what is going on signal wise or visually within the console or the software.

Very occasionally, a have a complete digital audio disaster (for lack of a better term), which is about a second's worth of terrible noise (unfortunately I run my master bus through MultiRack, so if it happens, it is REALLY audible), that I would speculate is due to the two systems dropping out of sync.

I have already tried quite a few things to find the problem: Swapped the fibers, USB cables, changed the buffer size (I started off at 64 samples). Also, I reboot the Mac before I run MultiRack.

Do you have any idea what else I could try?
Is there maybe a utility that I could run that documents clocking problems, so I can at least be sure it IS a clocking issue (it never happens with the 01v running on its own)?

I am frankly out of ideas, any help would be greatly appreciated.

Janko