pjsip: Handle NS initialization error consistently

Ignore-this: b2596663bac8f89ef483ad39c5715096

darcs-hash:20130716145807-56b4d-ec78ae1af60f4d7b5b66a1885e0b231f156ee878
pjsip: Cancel echo before suppressing noise

Ignore-this: 39038ce02dfdb70602a8d265e32a4a1f

darcs-hash:20130716145921-56b4d-6f1bcca95ad86b028d8c72e31b3f1589cdaa5267