Hahaha, ohhhh. Yeah. I did that when I was a kid. From what you're describing, it sounds like he, like me and many other aspies, could have a VERY difficult time transitioning from one activity from the next.
I would get REALLY into something, then my Mom would try to get me to change activity, I would throw a massive fit, eventually change activities, then get REALLY into whatever I transitioned into, then my Mom would try to get me to transition again, and I would throw another fit.
I just didn't want to stop doing whatever I was doing. I was SUPER into my own little world, and I didn't like it when people barged in and tried changing stuff. (I mean people have to. I needed to be live like a regular human being.)
This is just from speculation. It might be something else entirely, but if this IS the issue, then try to partition his time and give him plenty of forenotice before having him do something else so he can finish up his thoughts, making sure to have a clear time specified as to WHEN the transition will happen. If the problem IS transitions, then giving him a heads up, and a clear time he knows when a transition will occur before it happens, then it should calm him down being able to wrap up his thoughts or activities before the change happens.
If it's not just transitions, then I dunno. :/ But I would give it a try. This situation sounds a lot like how I used to behave as a kid.