Actually, I might have a solution, since your machine is the same generation as mine and I have had similar issues with my own Yamaha 8x that we made external ourselves.
There is one big issue with the external SCSI bus on our machines: it has a 5MB/sec theoretical limit. 8x CD burning runs at about 4.2MB/sec. If your computer chokes even a LITTLE, 8x will produce a coaster on me, even 30 seconds into the burn.
Try doing the following things:
- Make sure your cable is up to snuff like the previous poster suggested
- Put it as the SCSI device closest to the machine
- Tell Toast to use a larger RAM buffer (slower caching, but better burns)
- Try not to load your machine down with lots of CPU and/or I/O access while burning. Your bus can easily choke with the graphic data and CD data passing along the bus, you don't need to add more onto that if latency is key, like it is with CD burning.
If you follow these, you should have no problems burning at 6x. Your bus is a little more choked than mine most likely (the 8600 and 9600 had the largest bandwidth ratings out of the G2 series of PowerMacs), but you should be able to do just fine.
iMac G5 2.0Ghz (10.4.x, Main System)
MacBook 1.83Ghz (...Feburary)
"Sometimes I drive to run from all my demons \ Sometimes I drive so I can be alone \ Sometimes I drive to see the world in different light \ Sometimes I drive for no reason at all" - Assemblage 23, Drive