Janome 5700. Sometimes when I turn my machine on it makes a terrible noise like the needle hit

Question

Sometimes when I turn my machine on it makes a terrible noise like the needle hit something, but then I get an error message #1. If I'm persistant I can keep turning it on and then off and eventually it will come on as normal. I've brought it to the local that sold it to me and he thought he fixed it. Unfortunately he is about 90 yrs old, I'm afraid to bring it back, only to have the same problem over and over again. What could the problem be?