How can I get my SO to want to be more involved in my social life?

We’ve been together for a few years now and we have a very healthy relationship. We hardly ever fight and we’re usually very good about making decisions together. One of the few things that gets us angry at each other is his not wanting to do anything with my friends. He’s never said anything about disliking my friends, in fact, he usually has a great time when ever we do hang out with them. The hard part is just getting him out of the house!
Sometimes I feel that playing his video games is more important to him than going out and spending some time with friends. I guess I just wish he was more willing to do things outside of the house. Even going out just the two of us can be a problem sometimes.

What can I do so that this doesn’t turn into an argument all the time?