Could be interference if you are using it with a phone or near a phone. Phone reestablishes cellular connection and a corresponding crackle occurs. This happens to me if I am using an amp such as my Arrow or Leckerton with the iPhone, so I switched to amping my eight year old iPod and no crackle since. The periodic crackle issue with amp connected to phone occurs no matter which IEM I use.
Edit - congratulations on the IEM. You're experiencing what I meant in build quality. As to its design and fit, you can envision slipping the helmet on without getting hung up on wires sticking out of or from the ears. Or removing a helmet and it gets snagged on the same wires and yanks one or both IEM's from the ear.
If the isolation is a hassle, try a tip that doesn't seal as well, such as the included silicones. Or modify fit for slightly less seal. Even with maximum seal, it's something you'll get used to. These all require adjustment. I, for instance, am digging the Etymotic HF3 I got on sale the other week and it took a while to get used to the tips that work for me. Same with my MeElectronics A161P.