So doubletapping ctrl messes it up? I gamed on mine for a while, and I do lots of crouching/etc with control, and I never noticed something like that happen. I'll hook it up and test it again here in a sec.
Are you using it via USB or on PS2? Do you have an adaptor? Are you running some software that might get in the way (like sticky keys, accessibility?)
Probably the best question is: How easily can you return or RMA it?
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Just tried it with my CM in blues. I was tapping away pretty quick on that control, and it worked great. I also tried double bounces. Maybe using blues for FPS isn't that impossible....