[Dr.Sade]

Is the sound leakage of the Sony EX90LP entirely dependent on how it fits
and is positioned in your ear, or will it leak sound no matter what you do?

 

[azncookiecutter]

If they're anything like the EX 51/71s, then they'll leak sound no matter what. The EX-71s I had a while back had holes on the back to allow air into the driver, and I'm pretty sure it leaks sound from there.