How do I connect my MacBookPro to my external amp/speakers.
There's is no choice in sys pref to choose LINE OUT, only INTERNAL SPEAKERS.
The headphone jack is your combo headphone/line out. You use a mini plug on the MBP end and, depending on your external amp/speakers, either a mini jack or a pair of RCA jacks.
PS. Your OS X level can't be 10.3.7 ... MacBook Pro's were first delivered with OS X Tiger 10.4.
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