TriX creo tienes un problema...
Según Digidesign:
Pro Tools LE 7.4.2 for Mac OS X System Requirements
Pro Tools LE 7.4.2 for Mac OS X is a free update for Pro Tools LE 7.4 owners that adds compatibility with Leopard. For more information and link to downloads, please see the following:
Pro Tools 7.4.2 for Mac OS X 10.5.3 & 10.5.4 (Leopard)
Pro Tools LE 7.4.2 for Mac OS X has the following system requirements:
Installation Requirements
Mac OS X 10.5.3 or 10.5.4 (Leopard)
DVD drive required for Pro Tools LE 7.4.2 installation DVD
Not required for Download-only Pro Tools LE 7.4.2 installation
Pro Tools LE Audio Interface Required
Pro Tools LE 7.4.2 supports the following Digidesign audio devices:
003
003 Rack
003 Rack+
Digi 002
Digi 002 Rack
Mbox 2 Pro
Mbox 2
Mbox 2 Mini
Mbox 2 Micro
Mbox
Pro Tools LE software will not launch without one of the above Digidesign Pro Tools LE hardware interfaces connected. Please note:
Pro Tools LE supports the use of any single Pro Tools LE audio interface
Simultaneous use of multiple Pro Tools LE hardware devices is not supported
Maximum Sample Rate:
003, 003 Rack, 003 Rack+, Digi 002, Digi 002 Rack, Mbox 2 Pro - 96 kHz
Mbox 2, Mbox 2 Mini, Mbox 2 Micro, Mbox - 48 kHz
Supported Apple Computers
Pro Tools LE 7.4.2 for Mac OS X is qualified with the following:
Apple Intel-based Computers Supported with Pro Tools LE 7.4.2
Mac Pro
MacBook Pro
MacBook
iMac (Intel)
La solución que veo sólo es que te pongas un PT 8, ya que según tu sistema operativo es la que te funcionaría...esto pasa por no ver antes qué te va a pasar si subes el Osx. y si lo haces hazlo siempre de los Combos de Apple.
Pro Tools LE 8.0 for Mac OS X System Requirements
Pro Tools LE 8.0 for Mac OS X has the following system requirements:
Installation Requirements
Mac OS X 10.5.5 or higher (Leopard)
DVD drive required for Pro Tools LE 8.0 installation DVD
Not required for Download-only Pro Tools LE 8.0 installation
Pro Tools LE Audio Interface Required
Pro Tools LE 8.0 supports the following Digidesign LE audio devices:
FireWire Interface:
003
003 Rack
003 Rack+
Mbox 2 Pro
Digi 002
Digi 002 Rack
USB Interface:
Mbox 2
Mbox 2 Mini
Mbox 2 Micro
Mbox (original)
Pro Tools LE 8.0 software will not launch without one of the above Digidesign Pro Tools LE hardware interfaces connected. Please note:
Pro Tools LE supports the use of any single Pro Tools LE audio interface
Simultaneous use of multiple Pro Tools LE hardware devices is not supported
Maximum Sample Rate:
003, 003 Rack, 003 Rack+, Digi 002, Digi 002 Rack, Mbox 2 Pro - 96 kHz
Mbox 2, Mbox 2 Mini, Mbox 2 Micro, Mbox - 48 kHz
Supported Apple Computers
March 5, 2009 — On March 3rd, Apple, Inc. released new versions of the iMac, Mac mini, Mac Pro and MacBook Pro. Testing is underway and Digidesign is working toward fully qualifying these new machines. For the most recent information about Digidesign products and updates regarding the qualification of the new iMac, Mac mini, Mac Pro and MacBook Pro, please check the compatibility pages at the Digidesign web site.
Pro Tools LE 8.0 for Mac OS X is officially qualified with the following:
Apple Intel-based Computers Supported with Pro Tools LE 8.0
Mac Pro
All Mac Pro models are officially qualified up to but not including latest models announced March 3, 2009
MacBook Pro
All MacBook Pro models are officially qualified up to but not including latest models announced March 3, 2009
See below for information about MacBook Pro with FireWire 800 ports only
MacBook
Models with FireWire ports only, not supported with late 2008 USB-only models
See below for more information
iMac (Intel)
All iMac models are officially qualified up to but not including latest models announced March 3, 2009
Mac mini (Intel)
All Mac mini models are officially qualified up to but not including latest models announced March 3, 2009
En cuanto a lo de LogicPro8, ningún problema, debería funcionar como interface de audio.
Saludos