Nak ZX-9 Sensitivity/Bias regulators

Just bought the ZX-9.
I tried to do the adjusments but the knobs (which are in pairs, items 23 and 24 in the manual) are covered with some caps, which I cannot remove.
I am unwilling to force them unless I know how.

Anyone knows this?

Thanks, Mike.
Thanks for posting this. I have a Nak ZX-9 with the same issue. I hope someone has an answer. I use my CR7A more
often because of the higher output. I thought it was an
issue unique to my machine, but obviously it isn't.

I eventually was able to do this with my fingers.
It did hurt a little (my fingers that is), but I started with the leftmost top, where the access is the easiest, and pulled it off. Then the others came off too as access became easier, only one of them was tight.

Be careful when pulling the cap off, make it slide off slow, as sometimes some of the knobs it covers may be pulled off too, remaining in the cap (which is OK - you just put them back), and if at the point of disengaging the velocity is too much, the knobw may fly out and try to hide under some heavy furniture in the darkest possible corner, or even drop into the heating air duct.

I was warned so I did not have any accidents.