Adnectere

The car is a 2001 c5 - ever since it was bought, if you start in reverse, it doesn't seem to 'go' into reverse all the way, that last hump of the double hump it sometimes won't make when you start it in reverse and it does this weird spin up/howl/quasi grind thing if its not in all the way. Car currently has 19k on it and is still doing it. The best way to avoid it is to start the car in neutral and then shift over and that works 100% of the time, but if I start in reverse and then don't physically push the stick further into reverse it seems to do that noise. Ideas? (Also I read the sticky and I'm just not thinking it's air - the system has never been opened/modified and low miles on it. Search keeps going to google too.)