Cochlear Nucleus products provide the option to program a CI sound processor with several pre-processing strategies, which aim to improve the speech understanding performance in noisy environments. The goal of this study was to evaluate the performance of different pre-processing strategies in difficult listening environments. Two different speaker setups for speech understanding tests in background noise and two different type of noise were used. The tested combination of different preprocessing algorithms in Nucleus® CP810 provides better performance in less modulated background noise and in more realistic environments.