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If Logic Pro X crashes when you start playback before an ARA capture, the likeliest cause is that a VocALign Project or VocALign Pro plug-in is installed in your Mac, without a valid iLok license - possibly after a trial or an upgrade.
Remove "VocALignProjectAU.component" and/or "VocALignProAU.component" from Macintosh HD/Library/Audio/Plug-Ins/Components/ in your Mac and the crashes will stop.