Birch
100+ Head-Fier
I have tried with a decent amount of pressure, afraid that the plug will bend if i apply any more. Will try to get some leverage, maybe a quick spritz of deoxit to grease it up
From what everyone's saying, it sounds like that binding post is defective and wasn't machined properly. Too shallow(check depth with toothpick?), too narrow or both. Inserted partially may be sufficient(?) or you could remove the banana and use it bare wire. Replacing the post is an option but may be more effort than it's worth. (Drilling it out you risk spinning the post and removing any plating.)
(my .02 cents)
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