Gentlemen:
Found a couple of DUNNs in the 11th/17th Consolidated Arkansas Infantry (which Virgil has confirmed) DID have men from Amite County in it.
Their names/rank/units:
Dunn, T.J. ----Co. A 11th/17th Ark. Inf. Pvt/Pvt
(Dunn) ----Co. I 11th/17th Ark. Inf. Pvt/Pvt
Hope this helps some?
y.o.s,
Kenneth Byrd