Interconnects--How Important is a Tight RCA Fit?

I bought a new preamp and one of the inputs doesn't hold the RCA plug as tightly as the others....however, the contact is sufficient to produce continuous tightness here a big deal?
snug is fine...when to tight such as the old RS RCA plugs where you needed 2000lbs of pull to release there grip.They don't have to be super tight.Just a snug contact.
Snug is fine. You might try applying subtle presure to the RCA so that it closes or pinches in if the design allows for that such as barrell connectors or Monster turbine rca's or similar.
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The important thing to me is that the center pin is gripped tightly enough to make secure contact. If it isn't, you can't make it work better by tightening the outer portion. If the center pin is split, you can make it tighter by running an x-acto knife down the split. If not, I'd opt for a different connector.
you really want it pretty snug to avoid problems down the line due to corrosion/dirt/dust creeping in and reducing the contact area.