Danny, hope you don't mind posting some negatives towards those tubes. They don't grab the studs and too easy to pull out. Not sure it is a design issue or just a bad batch. I have more rants in my build log a few posts earlier on page 2.
Sounds like you made your hole a bit big. The hole should be such that you have to lightly tap them in with a hammer. Adding a little Silicone to them when installing keeps them from coming out (ever). If the hole is tight it also adds a little adding tension on the studs.
Still most are tight enough to require quite a push or pull to install or remove them.
I have used a ton of them and have yet to find any that didn't really gab on hard.
If you feel you got a defective one then feel free to send it back and I'll send you out some new ones. And if your hole is really that big then you might want to add a little Liquid Nails to the new ones when you install them. That will really hold them.