Harmonic Tech Magic Link 1 - won't fit rca jacks


I just bought a pair of Harmonic Tech Magic Link RCA interconnects on Audiogon. Problem is they refuse to slide into the jacks of both my (Rotel) CDP and (Classe) amp. Any ideas what may be wrong ? Thanks.
khwarezm
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What's interesting is that the locking RCA connectors that I've tried tighten by going counter-clockwise. Also, a word of caution: Do not over-tighten. Just make them snug. I know because I over-tightened one and it was a nightmare getting it off.
I know now what sherod meant. I did end up tightening them and then had to bring in a small wrench to grip and loosen them.