Hi,
It's hard to tell, if this is a problem at your or Arturias end.
Are you sure nothing at your end is causing the issue? Perhaps your powerplan settings, your internet connection or something else?
Have you tried to reinstall ASC?
Have you tried to download a single application through ASC? Or downloading a single standalone installer from Arturias website? Just to see, if that also fails.
If it's an issue on Arturias side, then i suggest you contact Arturia support.