The call wave sync watcher fired before DOM was updated (flush: 'pre'), so ref callbacks hadn't registered host elements yet. Changed to flush: 'post' so WaveSurfer instances are created after DOM refs exist. Also fixed getCallItem to read from clientTimelineItems (source of truth) instead of visibleThreadItems which could be stale. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>