When you switch from using one audio interface to another in GarageBand 2, you may come across a situation where your song plays back at its original tempo instead of your current one. This can occur if the interface you switched to wasn't turned on when you made the switch or wasn't connected when you started GarageBand, which causes GarageBand to switch to built-in audio support.
When you turn on the new audio interface or connect it while GarageBand is opened, GarageBand will ask if you want to use the new interface. If you choose to use it, your current song will play at its original tempo, which may or may not be your current one.
To avoid this issue, always make sure that your audio interface is connected and turned on before opening GarageBand. If you do need to change the selected audio interface, quit GarageBand, make your change, and then reopen GarageBand.
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