For best compatibility, be sure to downloaded the latest UAD1 driver from www.uaudio.com
* For improved performance when using a PCI-based audio I/O interface, install the UAD-1 and audio card on separate PCI busses. Slots 2 and 3 are on one bus, and slot 4 (furthest from AGP slot) is on a different bus. The 1.6GHz model has only one bus.

* At high UAD-1 DSP loads, inserting an additional UAD-1 plugin can cause a very high host CPU load and/or audio dropouts. The point at which this occurs can vary depending on the total number of UAD-1 plugins that are running. Additionally, some audio I/O interfaces may not allow UAD-1 CPU loads as high as those when using only built-in audio.

* Firewire and USB audio interfaces may not perform as well as PCI-based audio interfaces. High host loads and/or low UAD-1 DSP loads may result.

This is particularly true on G5 systems with more than one UAD-1 card installed. Performance may actually improve if you disable all but one installed card in the UAD-1 Meter System Information window. Multicard issues may also affect PCI and built-in audio (to a lesser degree than Firewire and USB)

Universal Audio is actively working on resolving multicard issues on G5 systems.