You need to update your H4 firmware. The Zoom site states: "The Zoom H4 will not mount as a USB Drive on MAC OS X 10.5.0 Leopard unless you update to H4 Firmware version 2.10 or higher."
Also the download would require me to copy the system.bin to the sd card, but the H4 is not showing up on my desktop to do that if I was using Leopard.
USB is working. I see the H4 is my System Profiler > USB
Just no desktop icon, or access in Audio Midi Setup
To use it as a interface plug it in with the H4 off. The usb will power it on, the display will ask if you want to connect as storage or I/F (interface) choose I/F then choose the frequency 44.1 and connect. Should be good to go.
Use a card reader to transfer the firmware file to the card.
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Zoom H4 Recorder
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