Quote:
Originally Posted by Hector Corrales Campos
....the "G" string sound very, very different and i don´t know why  . |
What do you mean by "very, very different"?
Two things I would consider first before any other assumptions:
1. It could be the G-string. Just because the strings are "fresh" or "new" doesn't guarantee against a faulty string. While it's rare, it does happen.
2. Has the bass been properly set-up?
Without having the bass in hand, it's difficult to determine what you could be experiencing. I would rule out No. 1 or 2 (above) first.