My Mackie Onyx 32.4 has no-latch XLR chassis receptacles too(28 females). Some Neutrik chassis receptacles have a spring retainer, instead of a latch. ie: (http://www.neutrik.com/en/xlr/a-series/nc3fah-0) If you can see the locking window(slot) in the male IC plug, you should be able to depress the spring with a small(jeweler's type) screwdriver, IF required. It's supposed to take 14.75lbs/ft(20N), to pull the plug from a(Neutrik) receptacle(without a screwdriver). IF NOT; Mr G offered good advice, regarding the manual/contacting the manufacturer. I've never seen a twist release, 3 pin XLR, but- I supposed anything's possible.