Well, there's a few mods on the site here that will void your warranty. And I don't know where that one person heard that the e2c is supposed to be bassy. It's exactly the opposite. It LACKS bass.
As far as the seal goes, there's a bunch of mods for that too. Custom IEM's, DIY IEM's, using swimmer's ear plugs, etc. I get a perfect seal with the foamies, myself.
Look around, there's a lot of advice about the e2c on the pages, and good luck!