Connect laptop to Bose PA

[bourgeoisdoor]

I have a Dell laptop that I have been running my shows on using Hoster. I have been coming out of the laptop with a 3.5mm, (the headphone jack output), and into my Bose Board, I think it's the L1 or L2 board.
My output jack must be beginning to fail. I tried a new cord but the connection is not good unless you twist the plug just right.
Is there another way to connect to my laptop? I do have a lot of other connection spots on this computer. I have 2 plugins for a backup stick.
Any ideas on a solution?

Thanks for your help,
Gary