I've had the machine for 1+ years now. And i can say that my feeders do not have this issue. They were also supplied from charmhigh.
It's a cheap chinese machine. So expectations should be handled accordingly.
I've had 1 pick head smash into my pcb because i did not set the pick height of a 7mm smd cap correctly. This mangled the hollow stepper shaft.
I've ordered 2 new ones and replaced it. No issue there.
I do have 1 feeder bank position that does not work, this is after 9 months of use. I assume that the valve / coil failed. Have not yet replaced that part.
The pressure reduction he put on the individual feeders is a fix he's using for the pressure. If you just decrease the flow of the air to the feeder, it will just reach the pressure more slowly, as he said.
Now, he can take the edge off with this reduction, but will need a non-return valve (don't know what it's called in english) in parallel over the reduction. So he only limits one direction.
That said, altering the individual feeder pneumatics is not the way to go.
On my feeders, the pressure at .6 MPa is just perfect. I've had some issues with the 24mm/16mm (can't remember) feeders in combination with a plastic usb-c connector.
In this case the plastic tape falls down on one side in the feeder. But hey, it's not a big deal.
Doing 0402 parts, which i almost always do, is pretty stable. Sometimes i have a resistor on it's side, but in the correct rotational direction.
On the most part, can't complain for the machine. It does what it needs to do for my needs.
IMHO, there is a lot of energy going on with the youtube making. Their experience is valuable. But it's a sample size of 1.
There are others out there that are using the machine successfully.
It's certainly no fun if you get the machine and there are issues, but, it's expected. Try and be creative, get to know the machine and do some manual pick/placing when required.