Yeah, so far the only idea I have is it's an account issue. I can play EXACTLY the same on my son's account, and never run out of ammo. He plays on mine? "Dad, how the hell do you kill so much stuff? you NEVER get ammo!"

That's incredibly odd... Though it does reaffirm my opinion that we aren't needing synths. It sounds like you've encountered an extremely rare bug. I'd either try and contact Bungie in some way to trouble shoot, OR - Test the method I've had to do to fix my achievement unlocks and see if it cures it. Level 20, all subclasses, the prestige achievement... None popped on completion. So what I did was go to settings, "switch account", sign into a different profile, pop THEM into the game, then "switch account" using their profile to go directly back to mine. All achievements then popped at once. Not sure if that would cure whatever you're experiencing, but it's worth a try?

I regularly take my profile to friends houses and play on their consoles, or swap between the three xbox ones in my house, hasn't made a difference so far. I can also say, I know at least one other friend who has the same problem, altho not quite as bad as me.

I did a Google search out of curiosity, but the only articles found were on D1 House of Wolves and prior. I'm sorry to hear about that, that's definitely a problem. Across the board, I don't think ammo synths should be needed still - whatever you have is unique and needs fixed. How is the question... I would say try redownloading the game or clearing your console cache, but if it happens elsewhere that idea is out the window... I'm unsure :/ do you have multiple characters?

Yep, Warlock and Titan, worst on the Titan, but not really appreciably better on the Warlock. Basically, the Titan needs to jump off a cliff regularly, while on my warlock I can sometimes punch my way to ammo. Funny enough, never had this problem in D1, my only "problem" with it was just bad luck with rng rolls for raid drops :) (It felt like I got Fatebringer every single time I did Vault of Glass, but I never got the pulse rifle, fusion rifle, or rocket launcher from VoG :P)

I've gotten the trials pulse 3 times, and the auto 3 times, in my one flawless run... I feel you. D1 it was always getting another Zhalo or Smite of Merain -_- but that's RNG for you. As to the issue, I'm really not sure what to say then? I was hoping maybe it was just the one character. Maybe try the switch character tab, but that's all I've got. Hopefully with the maintanence today they'll accidentally fix it for you.