Banana plugs into sockets - Lube up?

[Oddball]

Yes .
Silly question .
I have never used banana plugs at all until now !
Can anyone tell me if its quite usual for new fitted banana plugs to need a bit of silicone grease or similar , when using them in equipment that has not had those sort of plugs used on it ,before?
I purchased ten of each (black and red) so that I can fit them into the Marantz SR5600 with ease (trying to thread my soldered cable ends into each screw was more than tedious!

Trouble was , they were little buggers to push in ,although once in and out a few times (oooh err Mrs )were not so bad ! I was concerned at just how much pressure was needed to get them to go in.
Didn't want to break anything

I wondered if there was a little oxidation in the tubes ?

[struth]

Some are tighter than others Anto some lubricant can be helpful. Deoxit will initially help spray a little in hole and on the pin, then in out in out shake it all about

[Scooby]

Better tight than slack. Banana plugs and sockets often vary. I've had to prise a few open and nip a few others.

[Audio Al]

I like bananas