When I turn the key I hear a loud whining noise but car will not start

Is there any way you can get a recording of the noise? It sounds like the starter is not engaging and when you rock the vehicle it moves the flex plate and allows the starter to engage. However, the starter has a tapered cut gear so that it spins the flex plate as it engages to ensure it is able to mess. So this doesn't seem to make sense but I am not sure what else this could be. Hearing the noise will help identify what it could be. Thanks