【Swift】AVFoundationのフレームレート設定で落ちる

●現象
captureDevice?.activeVideoMinFrameDuration = CMTimeMake(1, 30)
みたいにフレームレート設定で落ちる

●対策
lockForConfiguration()とunlockForConfiguration()で挟むとOK

do {
    try captureDevice?.lockForConfiguration()
    // フレームレート設定
    captureDevice?.activeVideoMinFrameDuration = CMTimeMake(1, 30)
    captureDevice?.activeVideoMaxFrameDuration = CMTimeMake(1, 30)
    captureDevice?.unlockForConfiguration()
} catch _ { }