Installation stops in the middle

Hi!

I'm trying to install kali on my mac but in the middle of the installation, screen gets blue(not black so it is not totally turned off) and it sounds like it is working but then nothing happens. Then it stops working after 30 seconds it sounds like it is starting up again(haven't pressed anything) and some minutes later it stops again and now it has been quite for 10 minutes. Then I shut it down myself by holding the power off/on button, and then I come to the menu where you can use Graphical install again. But feels like the same thing will happen again and again. What can I do?

I can say that I have an old mac from 2010 so need to install Kali via DVD-drive instead of USB. Tried USB first but didn't work.

What was the problem with the USB?