I've found that when dealing with people somewhere else on the spectrum, i.e. closer to neurotypical, passive-agressiveness seems like a good solution, or at the very least a good way to convey annoyance, but it's never a way to cultivate understanding.

I think it's best to clearly state that this is something that you struggle with. There's tons of ways to find a solution, particularly with people you're around a lot, by first identifying what exactly the problem is.

But a simple tool to use when you're in a bit of a silent hang and you want to say something, rather than diving straight in with your main point (efficient but pointless if you have to repeat it), you can say something useless to grab attention. Something that doesn't need to repeating. Something like 'Hey can I tell you something'.

The thing is the reason they're not on constant alert may also be a sign of a disconnect somewhere. I've seen cases of people just not talking anymore because one person talked too much about stuff that the other didn't find interesting, so their default is not to really listen anymore. The 'this is probably going to be bullshit anyway'.

Then again, I'm not a therapist or trained in any of this stuff but it's just my two cents.