Learn English – What does “My duh on” mean

Well usually this is used when speaking face-to-face, and is taken to mean

I'm occupied right now, and I'll speak to you in some (short period of) time. 

Not exactly one minute, but a short enough time. Similar usage to "Just a second" or "Gimme a sec"

If on the phone, it should probably mean he'll call back after a minute or so.

Updated:

As @Martha says - On the phone, this would likely mean you should hold. The correct statement if he intends to ring you back would be

"I'll get back to you in a minute". 

Jamming into one's throat means to make absolutely sure the person hears you and cooperates with whatever you're jamming into his throat.

So the captain, Pat Rafter, is saying that he'll make absolutely sure his team gets the message that they can't afford to be complacent when playing against the Chinese. They've got to be tough, or they won't win.

And the point made in the other example is that most vegan/vegetarians don't force their views on everyone else, or even look down on others, as some people seem to think.

If you're planning to use this expression, consider a more common form: "shove down one's throat". This NGram illustrates that "shove down his throat", though rare, exists; whereas "jam into his throat" does not even appear. (The same goes for "their throats", and, I assume, all other forms.)