I just received my package of Slic Sound "covers" for in-the-ear headphones and while I like the idea, I'm not so sure about the fit.

I'm used to my custom-molded Musicians Plugs, that fit snugly right down in my ear canal. Now I know these aren't supposed to go quite that deep, but are they supposed to lock into the canal, or just kind of rest inside my ear?

I don't have small ears, but even with the smallest ones, I'm having trouble getting them to sit properly. They all just seem to rest in my ear, rather than "lock" in like they should. If I turn my head quickly, they'll fall out easily...

Any suggestions?

Thanks