Combat Frenzy suddenly not generating charges.

So I thought about it for a little and can think of the following: is it possible that by swapping your gear you maybe lost some int or dex and now your cast on crit or snipers mark has too high requirements for you?

Because as far as I can tell you should generate the charges with snipers mark and not combat frenzy while bossing since I don't think you are electrocuting right?

If that's not it, did you change anything else but the gear?

Can you update your character? You say you have changed gear, but it's not changed in the link. Also we need to see how your support gems are setup.

Why do you have Fire Infusion on your Herald of Thunder? It will make your Combat Frenzy work bad, because you reduce the lightning damage your Herald of Thunder does, hence you Electrocute less.

You do understand that Combat Frenzy does not generate charges for you on bosses? That's what CoC is there for.

Combat frenzy is for mapping. CoC is for boss/rare.

You are also specced into attacked speed before capping your crit? Attack speed does nothing for your spec, it's only there to help it feel smoother when mapping.
You can put snipers mark on your bar, to see how often it is proccing for you. But it has a cooldown, so it can only cast it every so often.

Are you all just forgetting that Combat Frenzy gives a charge on Pin as well, and it's a lot easier to pin bosses most of the time.

Is it possible you used to have the Pinpoint Critical support gem in Spear Stab that you removed? In any case, I would put pinpoint critical in Spear Stab. You want that skill to have as close to 100% chance to crit as possible so that you consistently proc CoC and consume Sniper’s Mark with it.

What is your crit chance with that skill, both with, and without Pinpoint Critical?

Have you actually read what combat frenzy does

Just wanted to mention that we are at a point where we are not even naming the build anymore.