1. Airport/Bluetooth and Energy Saver disabled?
2. Different USB port/cable?
Macbook Pro
The 15" MacBook Pro models have 1 USB port on the left side, and one USB port on the right side.
The 17" MacBook Pro models have 2 USB ports on the left side, and one USB port on the right side.
Due to internal USB architecture issues on the MacBook Pro, use of Digidesign, M-Audio, or third-party USB audio devices is supported on the left-hand USB ports only (the port or ports next to the power adapter cable).
*Use of such devices on the right-hand USB port is not advised because it may cause audio interrupts and/or dropped samples.
However, the use of an iLok on the right-hand port has been qualified and is fully supported.
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