My asd/very adhd kiddo does the same thing! I'm glad I'm not alone.
When he is on his meds, its more easy to manage.
I usually don't mind if it is just him and me and we're spending time together.
If I know we will be around other adults, then I explain that it is not appropriate right now.
It's gotten a little easier with time. He's 7 yrs old now. He's been doing that since he was about 5.