hey fellas...just started playing bass about a month ago(i'm a guitar convert, but determined to play like a bassist, not a convert). the band i'm in tunes guitars low to high c, g, c, f, a, d. for the first few weeks, i borrowed a four-string from a friend, and tuned just like the guitar players did. i recently purchased the 5 string traben havoc, and attempted to tune it like i did the four-string, with an additional low "A"(on the B string). i get a horrible fretboard rattle from it. I know there are dudes out there that down tune their basses, so my question is: what do you guys do? do i need thicker strings? proper setup? bite the bullet and re-learn a 25 song set(transposing with standard tuning)? any help would be greatly appreciated. thanks!