Do you have a second FW bus on a card, or are you plugging one device in the front and the other in the back? All the FW connections on the mac are one buss. If you plug in two devices, you may get a negative reaction. Not always, but sometimes. It can be intermittent.
John
MacPro 8-core 2.8GHz 8 GB RAM OS 10.5.5 QT7.5.5 Kona 3 Dual Cinema 23 ATI Radeon HD 3870
ATTO ExpressSAS R380 RAID Adapter, PDE Enclosure with 8-drive 6TB RAID 5
24″ TV-Logic Monitor
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