I never got a correct contact with them (on amplifier) resulting in un-balanced sound (left/right) and modified sound characteristics.
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Expand on this, please. What do you mean you didn't get a correct contact?
Was it tight enough going in or just flopped in and out?
If the plug was snug, no reason for any of your implications to happen in an audible manner, none.
As to sharing, everyone is free to do so. Just because an experience is questioned doesn't mean anything, only that it needs more explanation, or not. And, so what if others disregard it? Happens all the time.