Setup question (C string on a 6)

[el murdoque]

I've recently swapped strings on my Ibanez BTB 6 string bass. The new tension required a new setup. I've had the bass for nearly four years now and it still had the original setup, which was slightly askew anyway. So I got everything set to my liking,
with one tiny issue: The C string, when played in the higher registers (7th fret upwards), generates a tiny amount of fretbuzz. That happens when I play hard or when I fret a note and release it - it won't mute instantly but make a little noise beforehand.

Now what is the suggested course of action? Raise the saddle on the bridge?
Tweak the neck? If so, shall I make use of the dual trussrods and only turn the treble side one?

 

[Turnaround]

Adding more relief won’t really help above the 5th fret. So raise the saddle a bit.

 

[el murdoque]

will do, thanks.

 

[ixlramp]

Yes raise the saddle, as more neck relief does not reduce buzz for the higher frets. Also because you seem happy with everything else, altering neck relief will affect everything else.