Digibyte is a multi-algo coin. If you are solo mining, you have to set the mining algorithm to use in the wallet digibyte.conf file to one of the options. Like explained here:
https://bitcointalksearch.org/topic/m.10194594
algo=scrypt
algo=sha256d
algo=groestl
algo=qubit
algo=skein
You then can start the miner with the algorithm you chose and point it to the machine running your wallet RPC server. CGminer is a scrypt and SHA256d miner only. With SGminer you can mine any of the Digibyte algorithms.
If you are mining at a pool, you need to use a pool that is mining the same algorithm as the miner algorithm you choose.