Using M1 you cant use a browser to access/configure the slingbox so you have to use the program and it can be various things, for that I refer you to this link
The sling player app on my Macbook stopped working about a week ago. When I try to open the application, I get to the start screen showing the "Slingplayer" logo, but nothing further happens. The application is working fine on my iMac and my wife's Windows PC, but on the Macbook there is nothing. I have uninstalled and reinstalled the program a couple of times - no difference whatsoever.. Any suggestion would be appreciated!