Snare buzz is related to several factors. The tuned pitch of BOTH heads, the type of snares, the type of drum shell, the tension of the snares. I think what is really vibrating is the snare head, the snares are just amplifying the vibration. I've found it is not possible to eliminate it - you just change the frequency(s) it's sensitive to and how loud it is.
I like my snare sound lower than most (too much marching band) so mine tend to have the bottom head tuned higher than the top. Sometimes detuning one or more rods will help and heads with tone rings. Very thin snare heads are more sensitive than thicker ones. You can adjust the felt mufler if your snare has one.
Another thing to try is pre tuned snares. Rhythum Tech Active snares are ones you should check out. I use them on my set at church and they rarely buzz.
Good Luck!
Bob