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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i dont know whether they are the locking kind. i'll try that today when i get home. thanks.
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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.