maybe the Roland license for use their sound library in Quicktime Synthesizer is expired now.
And Quicktime Synthesizer itself has not been updated at all for almost 6 years or longer.
Quicktime 7 has a check box to play midi's. Quicktime doesn't have the same control panel that Quicktime 6 had, and to change the there Quicktime Music Synthesizer is no long an option.
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Quicktime Music Synthesizer
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