If she's not going to engage him or spend time with him...what is the point of putting him through the visitations. This is a HUGE parenting FAIL. She either needs to step up to the plate or sign away her parental rights.

She needs to take him on excursions somewhere. Canoeing, the zoo, museum, movie, amusement park, fishing. Something to occupy him other than his addiction.

I agree with the other comments stating that she needs to get him out of the house. It's bad enough to only see him a few times a year, she shouldn't let this visit pass without actually interacting with him.

It may be that the boy uses the gaming system as a shield because he fears rejection by this mom whom he sees so seldom. Mom needs to make a plan for a day that involves an outing and an adventure, even a lame adventure, sans electronics and take the kid somewhere. Even on a hike, if money is an issue. Mom may need to get assertive to get this going. But it has to be mom that does it.

do they have a good relationship if not you are just going to exacerbate any standing negative feelings its up to her to at least introduce a few days where they are not in the house and doing stuff together meal out cinema etc i imagine hes using his games system to keep in contact with friends at home

Sorry for your friend but this isn't your responsibility. He doesn't know you well and might see you approaching him as a threat and become more distant towards his mom.

Get him laid.

She's blowing it as a mom and you can't fix it for her. Instead of talking to him you might want to talk to her about parenting a teenager.

Think a better way is to invite to go toss a ball shoot a bow or even a board game do not get discouraged if he does not want to do it right away however some descriptive shuttle detail and this will help him be curious about the subject. I think if you enforce the spend time thing he could go rebellious.

No for sure.

You could help her come up with something interactive for them to do where electronics are not involved. Something he would enjoy. Teenagers are tough.

I'd try to talk to him some, but not about that. See if you can get him engaged or interested in something else, even briefly. Once you're talking, you can feel your way into the situation and maybe get an idea where he's at.

No, it's her responsibility to talk to her son about their relationship. It doesn't have to be a guilt trip or manipulation. I would vote against you getting involved.